This is clever.

I'm not sure why Dropbox doesn't offer plans with less space, and make it more affordable. For the $100/yr a 50GB account costs, you can get 100GB (plus unlimited storage of AAC/MP3 music) from Amazon via Cloud Drive. Granted, you're not getting Dropbox's excellent syncing, just storage (and streaming of music)

I'd be happy to give $20-25/yr to Dropbox for 20GB-25GB of space and syncing.