It's odd, really, for an instructional design firm, we are all-for not reinventing the wheel.  If there is training already "out there" and it fufills your need - even if you need to augment it a bit - why not take advantage of someone else's hard (and brilliant) work?

Here are some websites we've sourced recently, where you can find training offerings from A (Audacity) to Z (Zbrush).

Educator.com - From physics to music theory, Educator bills itself as  having the most comprehensive math and science content on the web. Pay monthly or annually for discount.

Edudemic.com - Lots of free resources and links to free resources. Geared toward teachers but their ideas and findings are really universal to anyone trying to be the best educator they can be.

Lynda.com - A video-based, on-demand, portal for software and business skills.  Pay monthly or annually for discount. Free trial.

KhanAcademy.org - Their tag line says it all, "Learn almost anything for free." The topics are more academically inclined and so would be ideal for assisting your workers with basic skills such as mathematics or sciences. Also video based in a really engaging delivery format.

And for some interesting factoids that you can use as icebreakers, energizers or to amuse, check out the Smithsonian's new website: www.SeriouslyAmazing.com.