eksites,
It's cool to have these ideas.
I think the part about taking a little laptop around Europe and being able to hit wifi spots in order to work is not realistic.
1st, did you take a laptop with you before while backpacking? It will be an easy target for theives. You will claim to be careful and probably will. But, at some point you will lose your guard and bye-bye laptop.
2nd the exchange rates just won't be in your favor.
If you really wanted to hit Europe again I'd plan on just working your ass off on building LOTS of free sites, and just save up enough money to stay there 3 months or whatever. Get someone to deposit your checks in the US and you can access your money via ATM.
Now, if you really wanted your money to go far you could look into SouthEast Asia.
Just a couple sales will cover 1 month's rent for an apartment. You've been to Europe. Go to Asia next.