TMF published an article at the end of 2010, running a mechanical screen. I wont tell you the shares they selected, you can read the article if you're interested, but I will tell you the screens they used.
Screen 1: PE<=9, PBV <= 1, NGR <= 30%, YLD1 >=3.5, EPG1 > 10%. 13 shares were returned.
Screen 2: PE<=12, PBV<=1.5, NGR <= 40%, YLD>= 4%, DC >=1.2; member of FT350. 5 shares were returned.
Screen 3: Widened (screen 2?) to search the FTSE All-Share index. An extra 15 shares were returned.
DC: Dividend cover
NGR: Net gearing
YLD1: Prospective dividend yield
EPG1: Prospective earnings per share growth
Their selections from the previous year's screen was up 42% (exc. divvies, dealing costs, etc.) compared to the market of +28%.