Fenix L2d with a red filter, Awsome for only using 2 aa batteries. I also have the HL20 head lamp that puts out 105 lumens on one AA battery. I don't think they sell them anymore so I'd check out the LD20 $59 205 lumens if you can get the red filter for it.
I use a coleman led flashlight from waly world for shooting rats. It comes with a red and blue filter lenses. I mounted it to a salvaged mount from an old night blaster light that no longer was working. The flashlight was well worth the money and throws a nice beam of light with the red lens. When the rats get smart to the red lens,switch to the blue lens. Before I came up with the mount I just banded the flashlight to the stock with bicycle innertube. crude but it worked.
I used a 3/4 pvc coupling epocied onto my fill cap. Then I glued a 3/4 - 1/2 in reducer bushing into that. I mounted a weaver base onto a 4 in piece of 1/2 in pvc, bolted a Streamlight TLR-1 onto the weaver base and slipped it into the 1/2 in end of the bushing on the fill cap. Do not glue the 1/2 in pipe to the bushing or you will not be able to remove the light without taking it off the weaver base. I added a pressure switch/tail cap and a red lens to mine. Work great and the lil darlings never know what hit em since the light is only on for a split second for the shot.
I just bought a Laser Genetics ( BSA Optics) ND-3, laser designater. I love it. It'll light up a critter 50 plus yards out using an 8-32x Bushnell 4200 scope. Can't say I like the adjustable scope mount that came with it. It shifts at the slightest touch. I do like that the laser came with a pressure switch, a camera mount as well as a mount ring for a picatinny / weaver rail. It all came with a cr123 battery and a padded zippered case. Good package. I put the streamlight back in the drawer......for now.
I just went all in and ordered a tac stock from Rob Taylor which arrived yesterday and is wonderful, and a Pulsar N550 Digisight, that is due this week. From the youtube postings, the N550 and the tac stock should be a serious threat to the local rat population. I'll lkeep you guys posted.