There is a thread on the BF Forum called Anyone fancy a lay a day which provides a very good source of fairly short priced lays. I entertain myself by laying their knocks for the place with a stop loss set at about 50% ( 2.50/ 1.75 ). I have noticed that when the Stop loss gets activated the horse almost always run a place. These guys are so good with their lays that many do not run a place.
URL is http://community.betfair.com/horse_...ncy-a-lay-a-day

One of the posters ( IwonIwon ) on the site has nominated 24 successful lays in a row and still going.