Blu is a new (to me) Twitter client designed by thirteen23 (who have some other really cool looking applications that I need to try out) for Windows Vista and Windows 7 users. It looks absolutely gorgeous and runs on .NET 3.5 (and not Adobe Air like TweetDeck and Seesmic). I’ve been using it for the past hour or two,and it is amazing how beautiful it looks,and how elegantly designed some of the functionality is. The opacity control with the thin white light that trails around the edge during a refresh are just some of the detailed touches that make this my current favourite twitter application,and a mighty fine contender to Tweetie on my Mac. Oh,and it’s free! (Honestly I can’t remember the last time I saw something this nice for Windows that was free).