This was recommended in another thread. It has a cap to put over the light because it's so bright. I've been in a brightly lit trauma bay and still get a good pupillary response.

Streamlight 65018 Stylus 3-AAAA LED Pen Light, Black with White Light 6-1/4-Inch https://www.amazon.com/dp/B00008BFS5/ref=cm_sw_r_cp_api_qUUvzbDS31JYC

Streamlight pen light - size of a penlight (fits in my pen pocket), brightness of an LED flashlight.

http://www.amazon.com/dp/B00008BFS5/ref=pe_175190_21431760_M2C_SC_dp_1

If you don't have one of these and you work a lot of DWI, you're missing out.

I decorate mine for holidays.

Also, I've noticed that several of our guys have invested in these lately. They seem to be pretty popular. I don't have one, but I can see how it'd be useful, especially if you work nights.

There is no better penlight than this one. It is the perfect pocket size.