Surely you've seen mods in the past, such as Counterstrike, a Mod of Half-Life. Or the "PSP version" of Half-Life, a mod of Doom. Or maybe you had some fun switching files in PC games.

Anyway, whatever you've seen or done in modding, what do you think of it? What are your thoughts on modding, its community, or mods you've seen?

Share or else.