Oh man, you guys are going way over the top..
I was wondering about weight and climbing, as I was losing over 100lb in the past 3 years..
I wanted to know how much better I would do if I had lost 20 more pounds, all other things stay equal.

So I made me a spreadsheet (excel) where I can plug in the route (length and vertical climb) and then compare the amount of work (in terms of "nn pounds, pushed up one foot, in one second")2 rider of different weight would do in order to climb that hill (you can play with weight and target time, to equalize the amount of work)...

Have fun.. (click here to download the spreadsheet)

as a bonus, this spreadsheet gives you also grade and angle of climb.. Remember, I have done this just for fun, and as a motivation (weight loss) tool, so please do go all out flaming the scientific merit of this thing..