My initial advice is to back off a little on pushing ideas at your boss if he's not receptive. Given the state of the economy and how many companies are faring, he may truly be constrained by resources and moreover may be more focused on just carrying out his core responsibilities rather than taking on new opportunities and risks.
That said, if you're creative and have good ideas, one thing you should do is start to figure out who in your company is responsible for developing new initiatives and businesses, and start to cultivate a relationship with them. Every company has someone like this, whether they're the head of business development or the new products person or someone who informally takes on these roles.
Once you've done this, you can get a better feel for what areas the company is looking for new ideas in and pitch accordingly. And the other main benefit of this approach is that if and when an idea of yours is picked up and you're asked to develop it, you can frame it as a situation where you've been asked for your thoughts because of your relationship with the new ideas people at your company, rather than that you were going over your boss's head and pitching ideas upstairs.
I once had a client at a consumer service company who had an idea for a new service that his boss just didn't like. My client was convinced it could work, though, and had developed enough of a relationship with the group president that he was able to comfortably bring the idea to her. She liked it and got a pilot team together to explore it, led by my former client. The critical thing was that the group president had enough clout to pursue the idea, and that my client had laid the groundwork for them to work together, which is how you should be thinking about your situation as well.