How can you start a science geek thread that will quickly spread to hundreds of replies, and long nostalgic trips down memory lane?

Post something about old HP calculators.  This morning there was a Slashdot posting about the HP12C financial calculator.  Very quickly this turned into a couple hundred postings about 29C’s, 15C’s, 16C’s, 41C/CV/CX and the venerable 48 series.

Then discussions about RPN versus algebraic.

Ah, I have three of these gems myself.  A 15C, a 41CV, and a 48GX.  I have a 15C emulator (that is amazingfly accurate) on my iPhone.

Geek heaven.