cheat sheets / technical resources that I use

vi:
http://www.nathael.org/Data/vi-vim-cheat-sheet.svg
http://blog.vgod.tw/wp-content/uploads/2009/12/vim-cheat-sheet-full.png
http://www.math.ucdavis.edu/~mathclub/cheat_sheets/vim-cheatsheet.png

bash:
http://blog.vgod.tw/wp-content/uploads/2009/12/vim-cheat-sheet-full.png

6.002:
http://www.mit.edu/~godoy/tbpcircuits.html
and Prof. Afridi's notes, which aren't available online

arduino:
http://sites.google.com/site/mechatronicsguy/arduinocheatsheet

spanish, 3rd year:
http://www.amphi.com/teachers/jinboden/3rdyearnotes.html

podcasts:
Spanish (all levels)
site: http://www.practicaespanol.com/es/ (AWESOME site, beats anything else I've seen hands down, wish there was a free resource like this for Chinese)
RSS: http://feeds.feedburner.com/practicaespanol

Chinese (ABC level)
site: http://aprilpodcast.blogspot.com/ (transcripts require a nominal fee)
RSS: http://feeds.feedburner.com/AprilsMandarinPodcast

Notes in Spanish Intermediate (Spanish III level, I think)
RSS: http://intnotesinspanish.libsyn.com/rss