While playing Halo: Reach a few days ago I found this glitch and its pretty bad ass. Sadly I wasn't able to play around with it more because a damn grunt threw a Sticky at me and ruined the fun.
Find the video by:
1) Loading up Reach
2) Going to Fileshare
3) Go to Custom Search
4) Search for "S7SWTF" - Dont ate the "s
5) Go to the glitch called "Bubble Shield // Jet Pack Floating"
Going to make a tutorial later on about it