While it's not one of my favorite Art Bell memories, my clearest memory is of Art announcing the stabbing of George Harrison. In an obvious state of disbelief, Art's words were, "First John Lennon, now George Harrison."
My favorite memory is, strangely enough, is of how f-ing scared I was the first time I heard Ed "Bullshit" Dames. Thankfully, I've grown up since then and learned to wipe my ass with anything Dames says. However, at the age of 16, wow was that scary.