I'm all about the rolling laptop case bags. Mine is big enough for text books, two laptops and overnight clothes. As you get older, you'll start having neck/back problems from those backpacks, especially if you only carry it over one shoulder or use a messenger bag type.
Something like this one is nice, but I've seen more fashionable ones than this too.
http://www.wayfair.com/UNITED-STATES...FYeo4AodZShm1w
There are tons of them here:
http://www.ebags.com/category/rollin...-bags/20030246