This mod lets you select other players by clicking on their nametags.
You can find two downloads on the files/earlier versions tab:
Left click: Allows you to left-click player nametags.
Both: Allows you to left and right click nametags. Right-click opens interaction menu.
Currently doesn't support clicking on NPC's or pets...should it?
Install: unzip to SWL\Data\Gui\Custom\FlashUninstall: delete SWL\Data\Gui\Custom\Flash\ClickableNametags