Forum member dopefish created a widescreen patch that is usable in BF2, BF2142 and BioShock. You can get hit his personal page for the hack here, where he maintains a full feature list and changelog. You can join in this discussion thread in the forums. The patch is allowed by Punk-Buster. Though not officially supported, EvenBalance and EA have both confirmed it is allowed.
The latest released version is v2.3.59
The list currently supported games