Blackburn Mars
Mars Magnetic Light
$15
This light has a versatile mounting mechanism: it can magnetically clip to fabrics such as backpack and messenger bag straps, and it can also mount to seatposts and frames by a silicone band.
Mars 4.0
$25
Mars 3.0
$19
In addition to five red LEDs, this light has two amber side LEDs for increased visibility.
Mars 1.1
$15
3-LED light with steady, flash, and chase modes.