I'm googling for them at the minute, but I'd like to run what I find through the filter of more experienced magicians. Does anyone perform exercises to improve their peripheral vision and, if so, which do you recommend? It seems to me that it would be a useful skill to develop in all sorts of magical applications.

Like, for example, is this any good? http://www.helium.com/items/1439589-tips......l-vision

Thanks in advance.