I looked at the U205, and although the screen is a bit small, it is very high quality. I ended up buying a 14" M105, mainly because it was much cheaper, but the screen on the U205 was clearly better. If you really need portability, it seems like a great machine. The one thing I thought was definitely too small on the U205 was the touchpad. It looks like it has a 4:3 aspect ratio even though the display is widescreen, which doesn't make sense.
Regarding the original poster's question, I don't think there is any built-in software to control the fan speeds. You can use the Toshiba Power Saver control panel to control the CPU speed, which will indirectly affect the fan. On my M105, it was configured by default to run the CPU and full speed when plugged in. I changed it to use dynamic speed switching to keep the machine cooler and quieter. There are also 3rd party programs with give you direct control of the fans. I don' know which ones work on the U205, but popular programs include Speedfan, Notebook Hardware Control, and RM Clock. The later 2 allow you to "undervolt" your CPU, which can also give cooler/quieter operation.