a number of people I've talked to have used this - (ding king)
(or other similar products)
to remove dings. I thought it looked cheesy (being on tv), but I really haven't heard bad stuff about it. I wouldn't hesitate spending like 20 bucks or whatever to test this out. I know others said it saved them from having to get theirs fixed by a shop. Some said it reduced the ding after like 10 tries - or after they figured out how much glue to apply. Others I heard say it pulled most dings out completely or at least 90% of the way flat.
If it's a huge major ding - majorly creased - it might not pop.