Miata is my vote too.
Like you I had no real desire to own one - but after riding in a spec and then a totally done over one with a v8 and aero I have to admit, those things are a blast. The fastest laps I usually run in my M come after riding in miatas. They really hone your skills and as said above- due to their light weight, consumables will last a long time.
2012 - 5.2L R8 v10, 6MT
2011 - 4.0L E92 M3, 6MT
2002 - 3.6L 996 Carrera 4S, 6MT
2004 - 2.2L Honda S2000 , 6MT