Something I haven't seen mentioned (here, or anywhere very often) - a large, solid vice with a good sized area to pound on.
Mount this on a solid work bench - there are times you want something completely immobilized (and not just victims). Yep, Use that one...It's amust when you don't feel like dragging out the drill press
I'll throw in another vote for a Dremel rotary tool - especially with the Flex-Shaft extension (and I do recommend an actual Dremel, compared to a cheaper substitute - I've had both, and the Dremel is still going long after others have fallen apart).
Of all the tools I use, this is tied with my cordless drill for most used. Have had one for many years, never used it. Thought I was going to make toumbstones
I use Makita for my drills - both cordless and on a cord. I can't recommend them enough. They've never let me down (Not gonna pick a brand on drills, but I have several of these and use them all the time. I rarely use nails so everything is screwed together. Always have one with a pilot bit and another with a Phillips head ready to go)
Some other tools I have:
Band saw - used extensively ( would like one of these, no place to put it)
Drill press - not used as much as hand drills. (Bought one four years ago....still in the box...don't do enough repetitive drilling to make it worth it.)
Router - small table top set up. (Have one, don't use it...If I build another funeral carriage, I will break it out and use extensively on the wheels)
Table saw - for big jobs. Always treat this one with respect. (Yep...scary SOB..Have one haven't used it in about 6 years.)
Disk sander - love this thing. Talk about taking the tedium out of sanding (Don't have one...not necessary for me as I haven't built anything that I feel needs sanded.)
Air compressor - always a new use for this around the house as well. (Have one, use for pneumatic props, need to get some tools for it for non Halloween projects)
Reciprocating saw - so many different blades, so many things to cut. (Love this bad boy...have gone through a couple cutting down pallets)
Angle grinder - once again, different disks for many different materials make this a versatile tool. (used to use to cut rebar, now use a little chop saw from Harbor Freight)
Jigsaw - cutting curves, interchangeable blades. (THIS..SO MUCH THIS!!!! Couldn't do halloween without it.)
Lots more - stopping now. List too long as is.