Started off by Robert Watson back in 1996, the Mod Archive is an archive containing a vast amount of tracked mods, and accepts formats like .MOD, .S3M, .STM, .IT, .MTM and .XM.
Everyone can upload their work to the Mod Archive, even without registration. Recently uploaded files are saved in a temporary directory, where they wait for one of the so called filterers to listen and check for quality. If it is accepted it goes to the letter directories.
If a person has 4 or more of his files in the letter directories on the Mod Archive, he can register as an artist, and have his/her own artist page with a listing of songs and an area where he/she can put anything he/she might want to say.
Since the Mod Archive contains more than 20000 modules, it's quite hard to find what you want, and even worse is finding the good stuff. To help avoid this problem, all tunes in the archive can be reviewed. A review contains a musical and a technical description of the song, a 1 to 10 rating, and a specification of genre.
Reviewing is done by the public, though registration is needed to be allowed to review. This to ensure that the reviews are appropriate.
The Mod Archive site also provides the users with a simple message board, where people can discuss any topic they like. This can also be used to get in touch with the administrators of the site.
You can find the Mod Archive at: http://www.modarchive.com/