OK, I admit, this has nothing to do with category theory, but maybe one of my mates out there can help me ... Did any of the readers of "categories" own (or use) a programmable calculator in the 1970s? I'm looking for something that would have done about 100 to 1000 instructions per second, with conditional instructions, loops and indexed access to numbered memories. The reason s that I want to set a exam question about elementary ideas of complexity along the lines of "The XY99 calculator could execute this algorithm for a problem size up to nnnn - how big a problem could you solve today with your million-times faster computer?". Info about performance, price, the year it went on the market, etc please, by direct email to me. (OK, I'll summarise the responses I get in another message to "categories".) Paul