Might as well post mine :
HP desktop calculators and computers (or is that 'hp calcs'?)
Old Computers in general. No, not 486 PCs, but things like PDP8s, PDP11s, PERQs, Philips P800s, anything I can understand at gate level.
Electronics. All electronics. Valves, transistors, ICs, etc. Building, repairing, tweaking, etc. I do have an amateur radio license, but I'm not active, and I'd rather not post the callsign.
Clocks/timekeeping. Everything from sundials to atomic clocks. One of my aims is to make a mechanical clock from scratch (and not just follow a published design, but design the thing too).
Film photography.
And related to that : Repairing cameras. Everything from sub-miniature to large format.
Home shop machining. There's not really a UK term for this, the closest is 'model engineering', but I don't really want to make models. I mean using machine tools at home to make stuff.
I hesistate to mention this one, but I love my cat :-)
Things I am NOT interested in :
Anything athletic/sporting. Neither taking part nor watching.
Pseudoscience/occult/related mumbo-jumbo.
Science fiction. Science fact is quite entertaining enough :-)
Making money. Sure I want to be able to enjoy my interests, but my aim is not to have a large bank balance
Religion. I don't want to get in a flame war, suffice it to say that your beliefs are your business, and I'll happily respect that. Just don't expect me to share them.