Sometimes you just want to share code between computers without committing it.

Does Git have an easy way to share "uncommitted" code that doesn't involve committing it on a branch and rebaseing it later?

I say this as a huge fan of Git, that's one scenario where a Dropbox folder is stronger than Git

Dropbox is for whatever I want to put in it. Including code! Just because I keep my project folders inside of Dropbox doesn't mean i'm not using git.