The 48h/jam badges come in 80 varieties each; for every category (overall, innovation, theme, fun, audio, graphics, mood, humor) there's badges for 1st, 2nd, 3rd, top 5, top 10, top 1%, top 2%, top 5%, top 10% and top 25% badges.
..So, if you're in the jam, and you place at 52 (or less) in fun, you can say you're in the top 5% in fun. Yes, this means that in jam, the "top 1%" and "top 10" are equal.
Usage: feel free to use the badges wherever and however you wish. However, DO NOT LINK DIRECTLY, instead, save a copy and host it yourself. I will enforce this by taking the files offline at some point and replacing them with a zip that contains everything.
Finally, here's some all-new badges that should cover just about everyone:
Ludum Dare Charts | My LD #30 entry | My schtuphh in general