So
a video was posted to YouTube (supposedly) showing an easter egg in the N64 verison of Super Smash Brothers allowing you to play as Master Hand!
This story appeared on the front page of digg.com, causing much hope and speculation.
http://digg.com/videos_gaming/New_Secret_From_The_Original_N64_Version_of_Super_Smash_Bro_1999
Unfortunately this is a fake. The video was obviously shot with an emulator and the most popular N64 emulator just so happens to have a cheat built in allowing you to play as master hand.
Pics of the cheat in action follow. Click either picture to pop-up the full-sized original.
Sorry to burst everyone's bubble :(
- Fox