I've heard quite good things about Furman's products, and some of them are quite inexpensive. I've seen a number of them in various bands/venues racks of fancy pants (read lots-o-$$$) electronics. One of my buddies has this one and likes it quite a lot.
https://www.amazon.com/gp/product/B0009GI7NC/ref=s9_acsd_al_bw_c_x_1_w
I was talking to one of the reps of a very high-end audio store here in Denver recently about power conditioning, and one of the cool features that a few of the furman ones have (I don't remember exactly which, but I can check) is the ability to boost your amp's power. By this, I mean that they have some capacitors inside that allow for a constant output of power regardless of fluctuations in the mains, and can also provide a bit more oompf if the amp needs it for a particularly dynamic section of music. I think that this is mostly geared towards people with speaker setups though, and may not be as useful for people in headphone-land. Though if you live in California and are plagued by brownouts, etc. then maybe it would be worth looking into, I'm not sure.
Also, aside from power conditioning, I have always had surge protectors of some sort on my amps, dacs, computers, etc. I have had two friends and my cousins' house all get hit with power surges or nearby lightning strikes that took out essentially every electronic thing they owned. Computers, phones, the lot. I can't afford to replace my nice stuff, so I use surge protectors on what I really want to keep
. Well, that's my two cents on the topic!
Also, some of the rack-mount power conditioners (across brands) have nifty little lights that pop out of the front (and sometimes the back) when you want some light on the subject.