I optimized the fan speed of my external SCSI tower. Often a slower, much more silent fan is enough to keep the temperature at an acceptable level. Check it with a logger. I'm sure you will have your own ideas, and I don't whether I remembered all I did already with it. Agreed, some application are a bit academical and not all the results are 'vital necessity', though, still quite interesting.
Some results are quite useful, others are just nice to know.
Availabiliy, price and an amazing hotsync adapter . Most of the development is finished and the final tests are running quite successfullly. But it's not yet available right now. I have still to do all the documentation. Another reason is, that I'm still not sure what options I should offer.