Geist by Taylor Engineering is really cool - it can operate two separate reels, one for thin thread, one for stage thread, or you can swap in an electromagnet coil instead. Remote controlled. Christopher's work is top notch - his electronics look like artwork to me. But it's $300 and up.
You kind of have to figure out what you are trying to display to really decide what direction to go. I used to bend metal, but at the risk of sounding like a hipster, it just got too mainstream. People were doing it without giving it the respect it needed to be a real mystery, so now it comes across as a magic trick unless you put serious work into avoiding that. The payoff isn't enough for me, personally.
I also used to do the occasional object-moving with IT but stopped doing that as well. For pretty much the same reasons as metal bending, but also because IT is a royal pain in my tuckus and I got tired of dealing with it.
Let's see - Oh yes, the Venom reels are good, too. If you want to work with IT I think those guys took a significant step forward in methodology. Arthur has some really solid work on that instructional video. You can use other reels as well, such as the Mini-Boss which is cheap - but I've also found it to be problematic.
It's hard to beat loops, though. Easy to hide, quick to use, lots of variety of effects you can pull off. If you get IET spools you can tie your own loops and make them any size you want/need.
Personally, the only PK effects I do any more are PK Touch-style routines, and as I've mentioned elsewhere - Banachek, Lior Manor, D'Angelo, Peter Turner, and Colin Cloud have the work on that plot published. Oh, and Luke Jermay. Each of them have more or less unique approaches (Peter's is strongly inspired by Luke's but I consider them unique enough to be separate entities). My own work on this plot is drifting more and more esoteric as I go. Actually, one of these days I have to look into Jerome Finley's Energetic Touches - I bet that's similar to what I've been moving towards.