[detaro]

Yes, they are for YC startups only. (When in doubt, its always best to email the mods about such things though - contact link is in the page footer)

[EnlightenedBro]

Hmm, thanks!

[gus_massa]

If you have an interesting project you can post it here anyway. Just ensure that it is minimally working, and add a comment explaining that you made it and some background info. (And be active in the thread to answer most of the questions.)