Recently started using a stir plate for my yeast starters and was surprised at how much faster my yeast propagates for pitching. This site (http://www.towercooler.com/index.php?option=com_content&view=article&id=65&Itemid=80) had alot of impressive info on their stir plates, which helped me out. I thought about making my own, instead opted for one of theirs and was glad I did. This plate can stir a 4 litre starter no problem, great for lager starters!! 
Wow, that’s more expensive than most.
Yeah, that’s why I made my own. Pricey buggers. Wasn’t overly difficult if you’ve ever done any sort of circuitry before (though for me it had been about 20 years, but hey, it’s not rocket science.)
Indeed . . I’m glad Alement is enjoying his stir plate, but $129 is definitely pricey. Don’t mean to burst his bubble, but I made 2 of these . . just add a computer fan, a few neo magnets, and a case and some basic assembly and you’re in for around $35 a whack . .
http://www.brewershardware.com/DIY-Stir-Plate-Circuit-Only-with-Power-Supply.html
I have two of these, as I brew ten gallons, but still use five gallon fermenters. They work great. I step up to 2000ml, with no problem.
Dan is also an AHA member and a member of our club. A really good guy, who’s hobby project got really big quickly. I have heard good things about his product online. I do not own one of those.
A friend gifted me a 9 position lab grade stir plate when he moved to the west coast. Thing must weigh 35 pounds!