RE: Binoculars under $100
I have a pair of Barska "Atlantic" 10x42 roof prism binoculars that I bought from Cabela's for $49 (they were on sale; now I think they're $59).
Nice binoculars, especially for the price.
If big binoculars don't bother you and you want to go really, really cheap, check out the Simmons 10x50 binoculars at Wal-Mart. I got a pair for $25 and they're pretty good for the money; their low-light performance is really surprising. They're big, though, which is why I went searching for something smaller.