Fluxiom goes a long a way to provide you with user interface elements you know and love from your desktop applications. Selecting files, even many at a time is a snap! With the rubberband selector you can select files in whatever pattern you wish.
The asset viewer also recognises:
⇧ (Shift key) + click to select a range of assets.
⌘ (Command key) + click on a Mac or Crtl + click on Windows to select multiple individual assets