[happy]

I think this site is also useful, recommend to you
http://www.rsc.org/chemistryworld/

[socraticjackie]

Socratic.org is launching their organic chemistry page soon (you can see its current state here: http://socratic.org/organic-chemistry/).  About half of the topics are linked to good youtube videos.  If you know of any other good youtube videos on orgo, let me know!

[lolgiro]

http://www2.chemistry.msu.edu/faculty/reusch/VirtTxtJml/Questions/problems.htm

My professor shared this link with us. Lots of practice problems on a variety of topics!

[java]

....its always good to know what some term mean...


Illustrated Glossary of Organic Chemistry

http://www.chem.ucla.edu/harding/IGOC/IGOC.html


..a great source to remind you what terms , reactions ...etc. ..java

[Archer]

I couldn't see this one in any of the other posts so apologies for duplication if I missed it.

Spectral database for organic compounds (SDBS)

http://sdbs.db.aist.go.jp/sdbs/cgi-bin/direct_frame_top.cgi

[chrisouyang8]

we always use www.molbase.com

[Dan]

A list of commercially available chiral units.

[caters]

https://www.khanacademy.org/science/organic-chemistry

This covers the basics of organic chemistry. However it is missing nomenclature and reactions of lots of oxygen containing functional groups,  quite a few nitrogen containing groups such as Azo compounds, some sulphur containing groups such as disulfides(which are similar to peroxides in structure because they have R-S-S-R' and peroxides have R-O-O-R'), phosphorus containing groups such as phosphate, and boron containing groups such as borinic acids and esters.

[Wrynn]

All kinds of courses (for free) including chemical ones:
https://www.coursera.org/courses?cats=chemistry

Chemical encyclopedias:
http://onlinelibrary.wiley.com/book/10.1002/14356007
http://www.scienceclarified.com/Co-Di/Cyclamate.html
http://www.infoplease.com/encyclopedia/1chem.html
http://www.sciencedirect.com/science/referenceworks/9780124437104

Organic chemistry:
http://www.masterorganicchemistry.com/resource-guide/
http://www2.chemistry.msu.edu/faculty/reusch/VirtTxtJml/intro1.htm