I use OptiPerl and Komodo3. Komodo's got a nicer interface, but it can be a little disconcerting going between both tools. K3's code explorer lists all scripts, not just the one you're currently editing. It doesn't have a built in web server -- which is something I really like about OptiPerl -- but it does have a Regex tester and support for other languages. In addition, you get Windows, Solaris and Linux versions with one license. (BTW if anyone's used an earlier version of Komodo before, v3 is lightyears better)