i don't have experience brute-forcing electrum, but the earlyer versions seemed to use aes encryption:
https://bitcointalk.org/index.php?topic=170188.0If you have a vague idear about what your password might have been, it shouldn't be to hard to write a little script to iterate trough your idears, add some letters, change some letters,...
Once again: the post above is for an old version, i have never attempted to execute this idear, so it might not work (anymore)