[sjs]

You can bring up Emacs' buffer list sorted with the most recently used at the top (bs-show). This is equivalent to alt-tab in the worst case. Because I can search this list (it's a standard Emacs buffer), I can get to anywhere in the end or middle far faster. You cannot see filenames in alt-tab until you select the icon.

Further, Emacs standard switch-to-buffer command selects the last visited file by default so you can flip between files with C-x b RET. Slightly longer than alt-tab, but not much once it becomes muscle memory.