Daily Crossword is an Ajax-driven crossword puzzle interface which can load Across Lite .puz format files from various places online.
Since I created this widget, many of the 'daily' sources of crossword puzzles have gone defunct. :(
You can find a small selection of Across Lite puzzle links at Krazydad.com. Also, the site Crossword Fiend has a selection of current Across Lite .puz links to use.