I just recently found out about this website, thanks to an awesome speedrun I saw by Norferzlo during the 2015 AGDQ... I don't know how I never thought to check for a community about this excellent game series, I have no excuse, but I'm here now.
My friends and I started playing Marble Blast Ultra for the Xbox 360 many years ago, and we were blown away by the incredible physics engine and the graphics are still a thing of beauty. We always challenged each other's times and we still start it up from time to time. But now that we've found out about this place, we'll hopefully get back into it full swing.
Through some drunken mishaps we discovered a lot of cool tricks and tech on a majority of the levels, such as platform clipping or 'trap launching'. That changed a lot of levels. It is unfortunately random as to what direction and how fast/slow you'll go, but it's so much fun to try.
So... Where should we start? I'm very excited to get back into this series, and I saw that there are quite a few different versions floating around out there. I'd like to try them all, but I'm unsure as to where to begin.