Logic Goats papercraft Answered

Here is a super cute little project which I found unaccredited on 4chan (who'd have thought?) Logic Goats! Papercraft logic gates in the shape of goats, which nod their head when the appropriate inputs are given. There are four (there may be others I haven't found):

I haven't made any of them up but I plan to this weekend! I'll post pix if I manage to do this :)

Update: these are from a website called robives.com, which sells them; I've removed these copies as they're clearly pirated. Thanks for pointing this out, meeze! I couldn't find attribution on the PDFs themselves yesterday but on checking again today, one does have the url on it and they're all on the site for purchase (see links above).

(Note about Internet safety. There is an attack which is becoming more common, which can be embedded in PDFs using the Javascript capability in Adobe Reader. I did a bit of research and I am confident that these Logic Goat PDFs don't contain any malicious code, but as with anything on the Internet, download at your own risk. In general it is wise to disable Javascript in Adobe Reader, if you use that for PDF viewing. There is an interesting discussion of one of these attacks here: http://isc.sans.org/diary.html?storyid=7867)