I wish vi fanbois and emacs die-hards stopped recommending them as Perl IDEs. They are editors, as much as you love them. They don't have debuggers, stack tracers, variable watching, breakpoints, regexp builders, or anything that makes up a real Perl IDE.

That said, Perl IDEs are listed at perlide.org.

There are two serious paid Perl IDEs:

• Komodo IDE. I've been using it and it works. Debugging is slower than in Eclipse+EPIC, but it does remote debugging. Development on Komodo is clunky (they still haven't implemented basic features like moving panes around, or tooltip variable evaluation, although users have been begging for them for years).
• Optiperl - I used it in 2006 and it was pretty good. I liked the tooltip evaluations and the cool background highlight of the blocks. But displaying complex data structures in the Watches pane was a mess: hashrefs can't be expanded and some display "REUSED_ADDRESS" instead of the actual hash; arrays of hashrefs were numbered in a totally idiotic way. For that reason, I stuck with Komodo. However, it's been 4 years since. Optiperl does remote debugging too, albeit with some issues. Its latest version, however, dates from February 2008, and it doesn't do Unicode. Komodo, by contrast, releases new betas all the time.

The two serious free Perl IDEs are Padre and Eclipse + the EPIC plugin.

I compared Komodo vs. Eclipse and stuck with Komodo because of its remote debugging capabilities.

Padre is still immature but the good part is that you can improve it, since it's written in Perl, unlike EPIC (written in Java).