NNTPGrab

Sadly, besides lots of interesting things, usenet if also full of fake shit. Here's my suggestion on a possible way to detect it:

1. When adding a new collection, detect if it contains any archive-like files. If not, skip fake detection.
2. If an archive is detected, download the first file of the archive (like .rar or .r00). Also download the .par2 to verify this file.
3. Try to unpack this first archive file:

• If it's passworded, ask the user if nntpgrab should continue downloading. Maybe offer an input box for the pw?
• If the biggest file from the unpack is another archive, consider the collection to be fake.
• If the first archive file cannot be unpacked but is corrupted according to par2, ask the user what to do.
• If the first archive file cannot be unpacked but is OK according to par2, consider the collection to be fake. (this is probably the second file of the archive, the first file being expected to be recovered using par2)
• If the biggest file is not an archive (maybe have a whitelist of commonly downloaded filetypes?), proceed downloading.

This wouldn't detect absolutely every fake (if somebody renames a cockring porn movie to "lord.of.the.rings.avi", what are you gonna do), but lots of rubbish could be detected this way I think.