This is, after all, the city that has not only been dubbed one of the hippest in Europe because of its raging nightlife, plethora of museums, independent art galleries and concert spaces, but it's also known for being wracked with debt. So much so that in 2003 Mayor Klaus Wowereit lent it the accidental slogan: "We're poor, but sexy."
GETTING AROUND: The BVG, which operates the trams, subways and buses, can whisk you from east to west Berlin for $2.65. It's a real bargain when you consider the lengths East Berliners once went to. A Berlin Welcome Card provides 48- or 72-hours of unlimited travel on public transportation for $21 and $27, respectively.
Of course if the weather's favorable, and you need to burn off the beer belly you acquired in Munich, Berlin is incredibly bicycle-friendly, with bike lanes on most major thoroughfares. Bike rentals tend to go for about $15 a day throughout the city. You can Plan your route online. Another option is the super-budget bike hire from Regenbogenfabrikfrom about $6 a day.
East Side Gallery: This brief stretch of the Berlin Wall along the River Spree features famous murals by international artists and has sadly suffered more recent additions by taggers (Warschauerstrasse S-Bahn).
Reichstag Dome: The glass dome atop Berlin's Parliament building offers dazzling views of the city, for free, and an opportunity to gawk at Germany's law makers below (S-Bahn Unter den Linden).
Schloss Charlottenburg/Sanssouci Grounds: If your less-than-royal status leaves you unwilling to pay the palace entrance fees, you can still loll in the lovely parks for nothing and pretend it's your backyard (U-Bahn Sophie-Charlotte Platz/ S-Bahn Potsdam).
Tiergarten: Get happily lost among the hundreds of trails sneaking through the park, which all seem to lead to the gleaming Victory Column in the center where President-elect Barack Obama enthralled a crowd of some 200,000 people back in July as he sought to burnish his foreign policy credentials. The trip apparently worked. Around dusk you may even spot a fox or two, and a few hours later, packs of white-booted prostitutes (it's legal in Germany) (U/S-Bahn Tiergarten).
Kaiser-Wilhelm Gedaechtnis Kirche: This bombed-out church makes no attempt to hide its scars - the contrast of its decapitated steeple and the serene stained glass of the new chapel are sobering testaments to the city's ongoing struggle to deal with the wounds of World War II (U-Bahn Wittenberg Platz).
City Tours: New Berlin Tours offers free citywide walking tours that leave from Brandenburg Gate at 11 a.m. and 1 p.m., http://www.newberlintours.com. The S-Bahn's elevated East-West Route through the city (S5, S3, S7, S75) is a great way to take in the sights from a seated position.
ENTERTAINMENT: When you tire of tourist-packed venues, the Landwehrkanal in southeast Kreuzberg is a soothing place to stroll. On a Tuesday or Friday afternoon, you can hit the Turkish Market for scarves and olives at bargain prices, then nap under weeping willows on the opposite bank (U-Bahn Kottbusser Tor). Treptower Park, Tiergarten's eastern sister, is ideal for an afternoon bike ride, particularly if you're staying in Kreuzberg or Friedrichshain, offering views of the Spree on one side and a spooky defunct amusement park on the other (S-Bahn Treptower Park).
Berlin is renowned for its nightlife, but you don't have to wait for three hours and pay a $25.50 entrance fee to have a good time.
Art Openings: Skulking around Mitte's galleries on a Thursday or Friday night you're guaranteed to spot openings with mediocre to mesmerizing art, and free, free-flowing red wine. Follow the sound of silvery laughter and the smell of cigarette smoke until you find a clump of artist-types slouching outside of a gallery like high schoolers in the school yard sneaking a smoke. Assume a look of pained condescension and elbow your way to the door. For a list of galleries, check out sites in English.
Spaetkauf Crawl: Take advantage of liberal liquor laws and sip as you stroll. Buy your poison of choice at a spaetkauf (convenience store), and don't forget to turn in your bottle at the next stop to reap your 19 cent refund.
Monarch Bar: Located above the large Kaiser's grocery store at Kottbusser Tor, Monarch charges a mere $1.25 entry fee, and is a great place to get your dance on. Enter through a dingy office door at 134 Skalitzerstrasse. Open weekend nights; things get started around 11 p.m. (U-Bahn Kottbusser Tor).
Claerchen's Ballhaus: Part wedding party, part "Strictly Ballroom," part hipster hangout, it all takes place under arched ceilings, ornate chandeliers, and gently crumbling wallpaper. A Berlin institution since 1913; $3.80 entrance fee on Friday and Saturdays; open daily, 24 August Strasse (U/S-Bahn Hallesches Tor).
Berliner Philharmoniker: With a student card you can score half-price tickets on unsold seats the day of the concert at the box office; with some luck you can purchase scalped tickets outside the building shortly before show time (S/U-Bahn Potsdamer Platz).
Vokue (Volks Kuechen): Serves hot meals in former squats, for a literal taste of Berlin's surviving punk scene. Check online for addresses and serving hours.
Weinerei: Four cozy locations in Prenzlauer Berg, Berlin's equivalent to Greenwich Village, offer a pay-as-you-please schema that, on top of the $1.25 cover charge, lets your conscience decide how much poorer you leave the place. German cuisine, made with organic ingredients, and a wide selection of wines. Open from 8 p.m. Veteranenstrasse 14, Griebenowstrasse 5, Kollwitzsstrasse 41 and Zionkirschessrasse 40 (U-Bahn Senefelder Platz).
Doener: The real Turkish delight. Little known fact: the shavings of roasted skewered meat, salad, and garlic sauce between bread was actually invented in Berlin. Since doener shops are open at all hours, one could eat doener for breakfast, lunch, and dinner, and still spend less than $12.70 - although the hospital bill might mitigate this. If you're vegetarian, just ask for "vegetarisch."
Currywurst: Berliners love their sliced sausage smothered in a curried ketchup sauce, preferably with fries. Available anywhere in town, although the classic Konnopke's Imbiss has been famous for serving it since 1930 at Schoenhauser Allee 44A (U-Bahn Eberswalderstrasse).
Fleischerei: If the odor of freshly slaughtered pig doesn't turn your stomach, butcher shops offer cheap, sturdy German meals like sauerkraut, potatoes, and sausage for about $5.
MUSEUMS: On Thursday nights, from 6 to 10 p.m. you can get in scot-free to the following state museums' permanent exhibitions: The New National Gallery, Picture Gallery, Museum of Photography, Pergamonmuseum, Altes Museum, Egyptian Museum, Old National Gallery, and Bode-Museum. On Mondays, the tiny Guggenheim Museum, located on the ground floor of the Deutsche Bank in Mitte, is free (S/U-Bahn Friedrichstrasse).
ACCOMMODATION: Rent an apartment, with rates starting around euro20 ($25.50) a night. The Circus Hostel, in Mitte, offers free Wi-Fi in all of its rooms, with dorm beds starting at $24.
For German speakers, more tips and daily free activities can be found online. Search under "eintritt frei".