I've been loaning them to other users and charging interest. Since there's not much to spend them on, I figure that'll stimulate the economy more than hoarding them.

By the way, I wanted to say this. If bitcoin is to survive, there must be a market that forms to accept them. The people who say bitcoins are deflating are not telling the whole truth. There's no way for bitcoin to deflate (well, except for losing them into the bitcoin blackhole, but that's another discussion all together). The only reason it appears to deflate is because of the inflation of other currencies at a faster rate than bitcoin. If bitcoin were to start being accepted to pay for goods and services, the flaws in fiat currencies currently in existence would become apparent as their inflation was made obvious in light of bitcoin's stability. And as long as people hoard bitcoins in order to trade them in for fiat currency, that will never change. Bitcoins will simply be an investment, and one that fluctuates wildly, rather than a stable currency in their own right.