Control-Tab and the ">of" trick are both useful. Neither of them quite work for me, though, especially when I've got a lot of open files or I want quicker access.
I like the free DPack collection of tools. There's a lot of neat stuff in there, some of which is built in to more recent versions of VS. I haven't seent anything like the file browser, though. It sits as a tool window (or dialog, if you prefer), and gives you an incrementally-filtered list of files in your solution. You can limit the list to open files if you use it as a modal dialog, apparently, though I haven't tried that.
(source: usysware.com)
