The cheapest and shortest shorts I have got are some Decathlon Kalenji ones. Seem to work fairly well, and I tend to wear them under my Jeans at work and then just drop my trousers to run home.
In reply to Roberttaylor: How about the more mile elite or roma split? Not sure about wind resistant, but I like my pair, and the more mile site has them listed at £8-10
In reply to Roberttaylor:
I personally like the nike ones, think theyre called team something. My size medium seems to sell out quick, think they are popular.