If you’re a front-end developer, you’re probably testing your sites with multiple versions of IE. (In late 2003, Joe Maddalone discovered a means of running multiple versions of Internet Explorer on a single machine, much to the relief of developers everywhere.) If you haven’t tried running multiple versions, check out PPK’s writeup at Quirksmode.org where you can download specific versions.
So, that gets you multiple versions of Internet Explorer, but how do you keep them apart? It can be easy to lose track of them if you have multiple versions open at the same time. One solution would be to make use of PPK’s “Keeping multiple IEs apart” script. Once added to a page, the script dynamically updates the page’s title tag to include the browser’s version number (in IE only). It works well and I’ve used it in the past; the only catch is that you have to remember to remove references to the script before publishing the page(s).
I also recently came across an article on Taming Your Multiple IE Standalones which goes over another solution. There, they link to a couple modified DLLs which add the version number to each IE’s titlebar. The installation couldn’t be easier — it’s just a matter of saving the directly-linked DLLs into your IE50 and IE55 directories, respectively. That’s it! Without even a reboot, you’ll have the version number within the titlebar of IE 5.0 and IE 5.5. IE 6 — the one integrated into your OS — remains unmodified (which I feel is safer) but you can deduce its version on Windows XP by its colorful toolbar icons.