Here's one I had somehow missed ... came across it when browsing for information on the "Bubblecar" unit - a heritage train that's running the Princes Risborough to Aylesbury main line services.

http://en.wikipedia.org/wiki/Aylesbury_Vale_Parkway_railway_station

I note that Buckinghamshire County Council is putting in a million pounds to this scheme (and the government rather more), which will provide an additonal "parkway" style station on an extended service that's 4 minutes journey to the North of Aylesbury.

I guess that Bucks is a richer county that Wiltshire - so much good could be done by having Westbury and Melksham acting as park and ride stations for commuters to Swindon, couldn't it?   There's no need for the Bucks infrastructure work either - just an extra train.