During my teenage years when I first started C++ (thank you Accelerated C++), I went to the ##c++ channel on Freenode and was immediately flamed for my "weird" nick, to the point that the people didn't bother to answer my question but instead went after me personally, just because I had picked a nick based on leet speak. I won't deny that it left a very bad impression on me about the open source community, especially as someone who was new to it.