My old Halfords light is a bit naff compared to some of the newer generation of lights but which one to go for?
[url= http://www.wiggle.co.uk/p/cycle/7/Knog_Skink_LED_Rear_Light/5360038178/ ]knog Skink[/url]
£14 at Fat tread
[url= http://direct.asda.com/Taillight-Nightshield/000953431,default,pd.html ]Clicky Thingy...[/url]
ASDA do an awesome triangular one for £6..
Big solid reflecter & light in the middle, with LEDs all around the edges.. Has about 5 different sequencies, and can been see for miles..
I got 2, and set them on different settings..
Had my Topeak Redlite for 4 years and still going strong.
http://www.allterraincycles.co.uk/product/8514.html
I got one of these from DX
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and it's very bright and ... a couple of quid posted!!
Knog Skink ticks the boxes here. Easy and quick to attach/remove and very bright.