Early this year we added a battery powered LED motion detecting light up our apartment's front stairway. It worked really well, scaring away the miscreants who often loitered around our area during late weekend nights...so well, that someone eventually stole it! We're still debating whether to replace it, but we might do it with one of these Solar Powered Courtesy Lights...
The Solar Powered Security Light from Gizoo is basically the same as the previous model, but with a nicer weather proof wedge design. The unit offers 8 meters lighting distance of detection within 100 degree angle; a 60 second LED illuminated light keeps your area lit up without the need for wires, thanks to a large solar panel ontop, making this a good stairway light. Available for about $48 from Gizoo.

White Enamel Flatwa...
I have one of these lights on the side of my house, and it works quite well. Provides a surprising amount of light, and it has a locking mechanism to make sure it can't be removed or tampered with.
Thorofin, the locking mechanism might have sold me. I can't believe someone actually climbed up and stole my previous LED light [waving cane with sour face].
I've been thinking about getting some of these for my house rather than installing hard wired flood lights. Has anyone tried any other solar powered security lights?
rmmarty: check the link in the first paragraph...I was very pleased with those lights before they were stolen.