In the dusk of this year's disappointing E3 2012 event, I hope you fans get something neat out of this.
I've recently rediscovered an ISO of a CD-ROM inside my old hard drive called the Next Generation September 1997. These were discs that were distributed into copies of Next Generation Magazine when you bought the magazine at the time. Included in the disc were lots of (low-quality 320x240) videos of PlayStation, Sega Saturn, & Nintendo 64 games that were featured at the Electronic Entertainment Expo (E3) on June 1997 in Atlantic, Georgia.
I've found many beta clips of many different games inside this particular disc including Crash Bandicoot 2: Cortex Strikes Back, Mega Man Neo (Legends), and Sonic R, all in their pre-release glory. The following videos have been edited to correct the contrast issues the videos had when it was first produced. They looked terrible (view this comparison: http://twitpic.com/9d1v6q).
This old early alpha gameplay footage of Crash Bandicoot 2 features several differences that indicate how early into production this game was when it was first announced in mid-1997. This video features annotations that go over said differences, including the original HUD font used from Crash 1, different object placements, etc..
This Sonic R Trailer footage features what appears to be a slightly (don't quote me, watch and decide for yourself) stage layout at the end of the stage. Different HUD (boy, this was publically a common beta game trait from those days huh?), and character icons, camera angles, etc. There might be a better quality version on YouTube somewhere, but I didn't find it until after this video was uploaded.
And finally, Mega Man Neo's trailer (which also includes annotations) can be found in an article on DASH Republic. Please visit the site and read our awesome article on the subject!
One more thing. I can't remember where I found the ISO in the internet, but in case the download source is no longer available...
Here you go.