Poor man's Down Low Glow?

[Eden]

I got a newsletter with this



in it - It's called the Firefly and its an LED lid for a standard wide mouth bottle.
( http://www.guyotdesigns.com/firefly )
I'm thinking paired with something like this



and you'd have a similar effect that could be put in your water bottle cage for about $35 or less (though it would be on the wrong side of the downtube to shine on the ground as much)