TextboxList turns normal textboxes into a widget which can be navigated with the keyboard, effectively turning your input into a “list” of items that can be easily deleted. It comes with an Autocomplete plugin.
On this page, you'll find help for the batch-mode del.icio.us bookmark editor, Scripted Re-Mark. You can see some simple examples, get a handle on the Tag Tidy function and "touched tags", understand regular expressions, perform a mass delete or get some tips and tricks.