The Pulsar is a pretty straightforward little LED keychain
light. Similar in size to a Photon, they are available with
an on-off switch for about $2 more.
It's small, light, and about as bright as a Photon, or any
other 2-2016 cell keychain light out there.
There was nothing really novel about this light, except that
the model reviewed was a limited edition run to benefit the
WTC victims and as such had a US flag on the side. Other than
that, it's pretty unremarkable.
The one unique feature it has for a keychain light is that
it will stand on its end, but that's pretty useless in the
models that don't have an on-off switch.
+ + + Pluses: Small, light, bright, no tools needed
for battery change.
- - - Minuses: Not water resistant, exposed LED vulnerable
to damage, relatively expensive coin cells