F-words (G-rated)

My job consists 20% of correspondence on a project called FABLE, which, being in the world of computer science is, of course, an acronym. I'll spare you the boring exposition and cut to the chase: the "F" in FABLE stands for "Fast", but unfortunately for us, our program is often... not so. Thus, for a half hour late this afternoon, a half dozen computer scientists (and the odd biochemist) found themselves brainstorming "F-words" that could appropriately replace "Fast" in their otherwise aptly-created acronym. Some suggestions (of many, mostly silly):

• ferocious
• flamboyant
• friendly
• fun
• felicitous
• frisky
  

Any more?