Guitar Riff
It's been noted by some that the central guitar riff in Nirvana's "Smells Like Teen Spirit" is very similar to that of Boston's "More Than A Feeling." But there are actually a couple of other songs I've noticed that use a similar riff (though it took me a long time to make the connection). Play the file below (requires QuickTime) to hear them and tell me if I'm just crazy (or if there are others I'm unaware of.