Portable QTWeb is a privacy enhanced web browser
Page load times are fast, and QT scored well on AcidTests (for what it's worth). Oddly enough, Webkit's SunSpider Java benchmark didn't complete. Resource usage is very respectable, typically less than or equal to Chrome with the same sites open.
Like most current browsers, QT includes a private browsing mode. Activate it, and QT will mask your user agent and make sure no local traces of your history are left behind.
I did experience a few rendering issues, though they were mostly limited to Flash-heavy sites. Most of the time a quick page down/page up would correct things.
Development is very active, with the most recent build coming just six days ago. Given some time to work out the bugs, QTWeb should become an excellent alternative browser. I wouldn't recommend QTWeb as an everyday browser just yet, but it's definitely a project worth watching.
In its present state. the portable version is only about 4mb and would still make a good addition to your USB flash drive or Windows PE disc. Source code is available from the QT Google Code project page.