Even with full internet access, I usually do:
- Study new language (Currently I am studying Ruby, Ruby on Rails and Scala)
- Study for certification (Currently I'm finishing my studies for SCBCD 5)
- Create personal applications (I've created two RoR application for my Wife's drugstore, they are working pretty well)
- Drink a lot of
coffee 
Regards, Jair Rillo Junior
http://www.jairrillo.com/blog, SCJA 1.0, SCJP 1.4, SCWCD 1.4, SCBCD 5.0, IBM SOA Associate (Test 664).