Got me a sous vide water oven for Christmas this year! It's pretty darn cool.
Basically, it's like a slow cooker but it allows you to set and maintain the temperature of the water bath very precisely (to within 1 F or 0.5 C). Using this method, you can make spare ribs cooked to medium but that still pull away cleanly from the bone, steaks that are cooked to medium-rare all the way through (instead of just in the middle), perfectly poached fish, etc... Of course, food cooked this way takes a long time (a medium-rare steak takes about 4 hours to cook), but because the temperature is controlled precisely and the food is maintained just above serving temperature, the timing "sweet spot" is a few hours wide (for example, the steak can be cooked to medium-rare and held there for up to 8 extra hours without loss of texture) so I'm going to be able to put food in the water oven before I leave for work and have it ready for me whenever I come home. One other thing is that you can't brown anything sous vide, but since the meat is cooked all the way through a quick sear in a very hot pan (about 30 seconds per side) will brown the meat and give me the best of both worlds. I can't wait to experiment with this thing!
If anyone is interested in trying this, you can make a cheap one at home by installing a PID controller in an old rice cooker or a slow cooker (plan are on the interwebz - where else?). Here's a guide to sous vide cooking with details on pathogen inactivation and cooking times, too: