If you're running a Linux box and your window manager feels to bloated? If you're bother with large configuration files and application windows which pop up randomly where they like? If You would love to group windows by tags and manage them in tiled, monocle or custom layouts? Or if you're just looking for a lightweight and fast window manager?
Than go for dwm!
Hold on! I'm maintaining udwm a fork with a few useful patches already applied. Right! Grab the latest snapshot and get your hands dirty.