I rip my DVDs to a hard drive, mostly because I have a computer hooked up to my TV and I don't have enough room to store tons of discs. If you get a nice bundle of discs and then sell them as a bundled set (minus boxed sets, which get a good amount on their own), you can make a nice profit from them.
I sold abut 200 DVDs on eBay as a bundle. I'd gotten each for about $5 at the local video store and a few for $1.50 - $3 from library sales and the Salvation Army (all major movies, hits, etc, no junk videos), the entire lot when for about $1200 on eBay, plus another $600 or so on the different box sets (Alias, Lost, Buffy, CSI, etc).
Considering two 500GB external hard drives only cost about $185 from Newegg.com....
I got a huge TV with my money