Not sure if my contributions count as a thread-jacking, but i will have to add my support to the Snowboard Addiction (and Snomie) video series. Went out for one last trip this season (by myself this time - normally go with my wife). I bought a bunch of protective gear (impact shorts, knee guards with inbuilt shin protectors, and a spine protector - ok so i am starting to get paranoid at my age), and decided to tackle the rail features...
It was actually one tip from one of the vids (cant remember which, but think it was the SA one) that really made everything click: "Make sure your body is perpendicular to the rail/box feature"
Once i had this in my mind (and the confidence from knowing i wouldnt smash my knees/tailbone if i fell), i progressed further than i had hoped to: Frontside boardslide (on flat boxes), Backside boardslide like a boss (flat, sloped, rainbow), spinning boardslides (flat boxes), 50-50s on flat and sloped rails, and backside railslides.
Still not sure if it gives the same rush as sticking a 20foot jump but sure feels great. This was most likely the last day of my season, but i will be buying the full SA set a month or 2 before next season starts (it will be too frustrating to watch over summer). Awesome vids!