Online Organic Chemistry Drawing Tool

I have some great news for anyone else who might be agonizing over organic chemistry!
My brain has been absorbing lots of organic chemistry in the past 24 hours in preparation for a midterm. Among my Internet travels, I have found the Molecular Property Explorer, which has been super handy for checking simple things like chirality and E/Z (which I somehow make mistakes on all the time!). It appears to be for pharmaceuticals or more hardcore o-chem stuff, but hey, it works for me. 
If it could do IUPAC naming on the fly, or show reaction mechanisms, they would make a lot of students really happy.
By the way, in case you can't tell (and it took me a while), those weird looking buttons at the top say "Clear" and "Undo".