The Bitcoin source is easy to fork, and people can make their own altcoins with relative ease. This site regularly sees questions from people who are having trouble with their custom coins, such as https://bitcoin.stackexchange.com/questions/21731/my-scrypt-altcoin-has-no-mainnet-hashrate.
My feeling is that such questions should be closed, as they are effectively asking the community to debug code that they can't see. I don't see how anyone could answer except to make wild guesses about what might be wrong, or to just say "Fire up gdb". But I'd like to see if there's a community consensus on this. If so, this meta question could become the canonical place to point posters of such questions, to explain why their question is being closed.
Edit: If nothing else, I propose a tag for such questions. Perhaps altcoin-development?