VM for fun and profit?
Easiest solution I could think of would be to have a VM to use for web browsing.
The choice of OS in the VM won't matter too much doing things this way - even if there is a disk space cost. But the disk space cost I think is minimal, as it doesn't really need backed up. If the VM gets malware'd to oblivion, you can simply nuke it and start fresh.
Better yet, have it snapshotted then revert to the snapshot when you're done. Snapshots could also be done following updates, patches, etc.
A small, ready-to-roll distibution like Damn Small Linux would be ideal for this kind of thing - less patching to worry about and fresh versions of the OS are a ~50MB download for the entire thing. Also snapshots would not really be needed - just boot from the ISO in the VM.