Let‘s talk about two interesting browsers for Mac, recently released but very promising: Stainless http://stainlessapp.com/
Cruz http://cruzapp.com/
The former, Stainless, is freely inspired by Google Chrome process management: you can open “single-session” tabs with separate cookies management.
Put simply, if your dream has always been to be able to log-in with two accounts simultaneously on a single site, with the Stainless you can. For example, for me that I run several ebay stores, Stainless is a fantastic opportunity.
Note that this version is very preliminary and weekly updated.
Give it a try.
The latter, Cruz comes from the same creator of Fluid.app.
The real peculiarity of Cruz ( based on WebKit) consists in being able to “split” the main window into three sub-windows: we can open two smaller side-windows rendered with Mobile Safari, and then, surf on iPhone optimized sites from our Mac.
It’s a very curious browser which could show interesting developments.