2167.
With American Idol ending this year, Fox has been reviving their retired franchises in an attempt to boost their ratings. They're currently testing that new business strategy with 6 new episodes of The X-Files, a series that ended in 2002. So far the first 2 episodes turned out to be a ratings success.
Fox also announced they're working on 10 new episodes of Prison Break, a series that ended in 2009 after 4 seasons. Wentworth Miller (Michael Scofield) and Dominic Purcell (Lincoln Burrows) are confirmed for that revival series, with Sarah Wayne Callies (Sara Tancredi) and Robert Knepper (Theodore "T-Bag" Bagwell) potentially returning.
The biggest announced revival from Fox, however, is a 24 reboot titled "24: Legacy," that takes place in the future and doesn't star Kiefer Sutherland (Jack Bauer), or any familiar faces. Unlike with The X-Files and Prison Break revivals, 24: Legacy is a long term project that could potentially run for multiple seasons.
Those three revivals are my top three most wanted from Fox. My most wanted unannounced revival is a Fringe mini-series, although that could be complicated because Bad Robot Productions and Warner Bros. Television produced that series.
Assuming Fox could make it happen, a Fringe mini-series could focus on Dr. Walter Bishop desperately trying to get back to the year 2015 after he learned of a disaster that took place during that year.
In an interesting note, Fox placed a character that looks like an Observer in their The X-Files mini-series trailer, as seen below at 1:38 through 1:40:
Honorable mention: A new season of Arrested Development would have been my most wanted unannounced revival, but I believe Netflix would have the exclusive rights to that season.
Question: What's your most wanted revival from Fox?