iTP A1 EOS SS (Cree XP-E R2 LED) light
My tiny iTP A1 keychain flashlight, which is no longer than my keys. This is the recent stainless steel version with the more powerful XP-E R2 Cree LED. A macro of the LED is available here.
The A1 is an affordable clone of the far more expensive 4Sevens Mini123 light. Though the Mini123 has a more advanced control system and a better LED, it's telling that all parts of the two lights are actually interchangeable.