Check out Mythic RPG at http://www.mythic.wordpr.com/page14/page14.html.
Here are my somewhat-simplified Fudge conversion:
1. Ask an in-game question, answerable by a YES or a NO.
2. Determine the Odds Modifiers:
Has to be +3
A Sure Thing +2
Likely +1
50/50 0
Unlikely -1
No Way -2
Impossible -3
3. To get the final answer, roll 4DF with modifiers:
- A Superb or higher is an EXCEPTIONAL YES.
- A Good to Great is a YES.
- A Fair can be MARGINAL YES, A YES with Complications, or Unresolved/Delayed answer
(Pick only 1 for the session/campaign) - A Mediocre to Poor is a NO.
- A Terrible or lower is an EXCEPTIONAL NO.