I really like this picture that I stumbled upon last week.
daemon-tux-duke-mozilla

I can see Tux, Beastie, Duke, Mozilla, OpenBSD, R. Stallman, GTK, Java, OpenOffice.org, GNU, Java, Apache. I don’t recognise the person between GNU and R. Stallman, neither am I sure what the camel is supposed to represent. If I’ve missed out any, let me know in the comments below.