You've raised a good question, and you've gotten a lot of great answers, so I won't bother you with repeated advice. Instead, I'd suggest not another language, but learn your editor of choice.

If you use vi or vim there is a vast wealth of power and utility, and once you start learning how to tap into it it will make a significant difference in your life every single day. Vi(m) scripts, perldo, folding, block editing, tagging and multi-file editing - these can really change the way you work for the better.

If you use emacs, then you have a wealth of power over data that simply boggles the mind. This editor attempts to do everything, and largely succeeds. As a byproduct of learning emacs, you'll likely learn LISP, so that's all right too.

If you are not using one of these editors, then start. They are the power tools - learning curves like the Matterhorn, but worth every minute of the climb.

Whatever you tackle next, good luck.