It depends on what you want it for...but as you say you have limited net time so I will give you a start. Try these:

1xCR123A $29.00
http://www.amondotech.com/index.asp?PageAction=VIEWPROD&ProdID=973

2xCR123A with a 2 stage switch low/high $42.50
http://www.amondotech.com/index.asp?PageAction=VIEWPROD&ProdID=816

or its brighter brother without the 2 stage $64.50
http://www.amondotech.com/index.asp?PageAction=VIEWPROD&ProdID=981

Although, if you want to burn retinas, I am told surefires are the best. Check out http://www.flashlightreviews.com for some excellent reviews.

P.S. I have no association with the linked sites in anyway shape or form.

Marc