I absolutely positively agree with you on this. Sure, all the one-word-hot-topic domain names are probably taken. But if you think about it you can still come up with some good ones. Two months ago I came up with a new, 3-word slogan for my site. I was shocked to find out that the phrase was available in .com, .net, .org and .us. The whole phrase is only ten characters long, so the names are short and it's not an awkward phrase. Apropos to this topic, I only purchased the .com and the .us, because I don't care so much for the others.
Another good place to check for decent available names is in the auctions. Among those million-dollar names that make you ask, "what are these people thinking?" you can also find some pretty good deals. I've seen for under $100, 3-letter .net names that would be really hot for Twitter/SMS applications. I've seen 3-letter .us names for under $20 that would be even better.