This year I got all the shooters I worked with last year (all 30 of 'em) a handy clip-on flashlight with a mini gooseneck on it.
Last year I got them wristbands. What? you say? Well, they don't use it for a wristband, they put it over the eyecup. It replaces the chamois leather one. It's soft on the face, doesn't muck up with sweat and when it gets dirty you don't throw it out (very wasteful and expensive over the year) you just drop it in the wash and you're good to go the next day.
Many of them report they're still using it a year later and it was the most useful item in their kit.
Best benefit? $1.95 each!