De veteranen weten het, maar alle n00bs zullen bij het zien van OSP toch afvragen "Wat is OSP?" OSP staat voor Orange Smoothie Productions. Een competitie Mod die bestaande games zoals Quake en Quake III beter maakt. Het zijn vaak kleine verbeteringen, fixes en aanvullingen die de gameplay nog fijner maken, maar de basis past OSP niet aan. Voor Return to Castle Wolfenstein is versie 0.21 uitgekomen.- Enhanced match mode play, utilizing player "ready-up" to force synchronized matches (all modes of play).

- Extensive in-game player and match statistics.

- Advanced and configurable voting system.

- Remote admin ("Referee") capabilities with many commands

available to control the match and players.

- Configurable client-side modifications that allow for extra visual settings.

- Ability for teams to "lock out" spectators to prevent giving

away strategy and cheating posibilities with Internet voice

communication mechanisms.

- Game "timeouts" for match play that allow for a pause in the

action (i.e. a lagged/crashed player).

- Enhanced UI with additional "tooltip" help information on added OSP

options.

- Enhanced latency support for laggier network connections.

- Truly random reinforcement time offsets on match starts. The respawn

times are still the same for each side on each map, but the offsets of

when they count down to 0 is now completely randomized.

Al met al genoeg verbeteringen om eens te proberen. OSP 0.21 voor Return to Castle Wolfenstein weegt net geen 2MB.