If there's one thing I hate it's serial connections and the monstrosity known as RS-232.
Whoever invented this beast I don't know, but the whole thing has caused me no end of trouble over the years.
For starters, there's the question of finding something that's got the right connector on it. OK, so there are reasonably common connectors like 9-pin and 25-pin, but then you have male and female, and Sun have at times combined two serial ports into one so you need a splitter. Modern systems might have RJ-45 connections. And then is it straight through or crossover? Whatever, it's a matter of luck if it ever works. Or sacrificing an intern or two.
But then there's older stuff - this morning we (ourselves plus Sun engineer) were trying to connect to the serial port on an A3500 controller, which has a 15-pin gadget that looks suspiciously like an old AUI ethernet port. Apparently there's a special cable that you can get if you are ever unfortunate enough to need to connect to the serial port on an A3500, but we don't have one. (For all I know, Sun might just have the one cable - I can imagine it being passed from engineer to engineer like an ancient relic, and who knows whether it was blessed or cursed.) So the A3500 is still sick.
Still, it could be worse. I reckon I'm cursed when it comes to serial connections, printers, and scanners. Trust me on this: you really wouldn't want me going anywhere near a fax machine!