Much as I love my Palm Centro smartphone (and before that, my Treo 650), it's almost criminal that it doesn't support voice dialing. Thankfully, there are several third-party utilities that add that coveted capability. From now until December 31, you can get VoiceDialIt for $15.95, a savings of 9 bucks off the regular price.
The software employs a simple, attractive interface for adding voice-dial contacts, either manually or from your address book. I installed VoiceDialIt on my Centro, and in about three minutes was voice-dialing my way to hands-free happiness. (I did, however, have to refer to the manual to figure out how to enable the trigger button. Fortunately, the manual is excellent.) VoiceDialIt is compatible with the Centro and all Palm OS Treo models, from the 600 to the 755p. There's also a version available for Windows Mobile Treos, though it's currently selling at full price ($24.95).