Best light going imho:
http://www.amazon.com/Verso-Recharge.../dp/B004D39RM2
Although Amazon only mentions that its suitable for Kindles, I used it with my T1 and now my T2 - great even light, no glare and adds little to the weight of the package and its rechargeable!
Video review:
http://www.youtube.com/watch?v=2EOtQXBzzk8
I used the Sony cover/light combo it was large, awkward, ate batteries and took a lot of fiddling to get an even flow of light on the screen without glare and hotspots. I have also used one of those gooseneck clip-ons and while better than the Sony combo, it was too large and over powered the reader's balance and it was difficult to get the clip secure on the reader without obscuring part of the screen.
If you want one you may have to hurry as I believe its been discontinued.
p