If at all needed, quality tools. You'd have to be fairly close to know that that 'goddamned department store square' is actually rhombohedral, but if you do and pick up a replacement from the likes of Lee Valley, you win the holidays.
If they don't have a tool-using hobby, they probably should, and you should get them classes thereon.
If they're already full up on heirloom-quality tools (and/or you can't afford them)... could you make them something? Home made is always worth points, if it is relevant.
Do you cook? Everyone loves the pickles and preserves we hand out; it's great bang for the buck, as long as you're dealing with folk who appreciate good food. Cakes and pies and sweets are also almost universally appreciated. If you knit, there's plenty of time to slap together a simple scarf. (If you don't knit, there may be time to learn by X-mas).
I'm not sure about savings accounts; the traditional investment gift is usually savings bonds, but if they're into this site they might be disappointed by the yield. I must say I think I'd be mostly just embarrassed if someone tried to gift me investments, but maybe that's just me.
I should also note that the holidays can be a good time for the frugal to get a hold of consumer goods they've been secretly pining for but unable to justify. Have you gotten any hints in that area?
