I had something more like this in mind. While it is not built to high end specs or materials, so long as the caps are discharged before testing, it should give ESR readings to a high degree of accuracy. It can also test coils and transistors and mosfets as well. I use a similar piece and has worked just fine.
http://www.ebay.com/itm/MK328-LCR-E...tance-Resistance-Meter-Portable-/321936118996
http://www.ebay.com/itm/MK328-LCR-E...tance-Resistance-Meter-Portable-/321936118996