The best solution: Two computers. One computer fast with lot of RAM and disk for your work and application programs, with no internet, no network, no antivirus, no firewall, no physical conection, you can remove the modem and network hardware from it, if you want you can kill IE too. The other, can be an old computer, with nothing except internet stuff, you don't need to worry too much about the hackers, there's nothing inside this computer. You can transfer downloaded stuff between the computers using RW Cdroms after scaned with some antivirus.

Stupidity also evolves!