Here is a DIY stirplate project for around $20.00 that anyone can make. You can build Screwy's Stirplate yourself and in a couple of hours and use it to start saving money on your yeast costs.
On of the ways to stretch my liquid yeast dollars is to create a 'starter' to ensure that the yeast I plan to use is viable and to increase the number of yeast cells before pitching them into my wort.
Radio Shack Parts List:
273-243 - 12 VDC Cooling Fan - 3 Inch
270-1806 - Project Enclosure - 6 x 4 x 2 Inches
64-1895 - 3/16 Inch Rare Earth Magnets - (2 Packages)
Click here for full build details...