has all OG (including the quant supplement) solved in video lessons. It is available for free. The beauty is how those problems are solved. They are solved in the most efficient way - cutting all the fluff. It also has all GMATPrep (tests 1 & 2) and GMATFocus problems solved in a similar way. IMHO, albeit the GMATPrep & GMATFocus solutions are not free, they present tremendous value to the GMAT community. I wish I had discovered the site soon enough and had time to use it properly before my GMAT. Hope this helps a fellow GMATter
Disclaimer: I have no affiliation with the GMATQuantum. Register for free and test drive yourself.