[Fucking stupid] Bad programming ideas [WTF]

Here's a thread where you can post retarded software/programming related ideas you read or saw on the internets. Retarded code from ENTERPRISE is fine too, but please don't turn this into “Retards writing Java” thread. You can think of it as /prog/'s own DailyWTF, only with less Java programmers and people laughing at stuff that they really don't understand. I'll start with a post from /a/:

I have been thinking about a P2P client which requests bytes from people who may not necessarily have the file they're downloading, but they have those specific bytes (which may be from another file), and the P2P client is designed to request the closed peer with those bytes, despite not having the file. So, it wouldn't matter if a torrent was dead, you'd just have to search other peers for those specific bytes.

It would have to be some sort of index of hashes of those bytes which would determine who sent them...

In other words, even if you had the computing power to enumerate all the files that hash to a particular value, you'd still have the problem of choosing the real original file among many plausible candidates, despite the fact that its length is known.

Are there any old, broken hashes or checksums for which you can iterate all possible inputs of a fixed length that fulfill them without going brute force?  I'm thinking about small lengths, like 16 bytes with obviously a smaller hash.

>>47
there's md4, which is (obviously) like md5, except presumably shitter in some way i don't really know

>>44
Yes but you can trim those possibilities down for files that have a distinguishable file format, such as AVI and BMP.