What mathematical function starts slow, explodes, and then plateaus?

This is a really bad web site. The page loaded, I saw the poll for a few seconds then it (apparently) redirected my browser to a blank page that took a long time to load. I could see the poll again, for a few seconds at a time, by repeatedly pressing the Back button. (I'm using Firefox 3.6.23)

Several of the formulas presented I don't know the curve off-hand, but none looked like it matched. The closest I can think of is x = y ^ 3 which approximates a logistic (S) curve; starts slow, rises steeply, then slows again, though it doesn't "plateau". Actually, an odd integer greater than 3 would lead to a steeper rise and flatter plateau, the bigger the integer the better.