Yeah bidding on your on auctions to get the price is called 'shill bidding' and it's against the rules of eBay. Info about it
here.
Nothing wrong with waiting till the last moments of an auction to bid though, I use that tactic all the time.
In fact there is a website that let's you place bid automatically at the end of auctions -
http://www.auctionstealer.co.uk/
They let you have three free 'snipes' a week.