The d20 System, d20 Modern, d20 Future, D&D 3.x, Pathfinder RPG, and associated games such as Prime Directive d20, or even Traveller20 (T20), have tons of open gaming content which you can use directly in your W.O.I.N. games after a little conversion. You'll find the d20 Modern SRD here and the Fantasy d20 SRD here. If something already exists in W.O.I.N., use the W.O.I.N. version instead.

Universal Dice Conversions

This applies to any game. Use the chart below to convert dice to d6s.

For values not on this list, simply take the maximum damage and divide it by 6 to determine how many d6s it is equivalent to. Add half the remainder (round up) as a flat bonus. 1d6 is the minimum.

General d20 Statistical Stuff

Where bonuses or checks are noted, adjustments convert as follows.

d20 Modern Purchase DC/Cost

To convert a purchase DC to a dollar or credits cost, simply use the following table.

FASA Starships

Converted ships use an abbreviated stat block.

Construction Data

• Convert directly. FASA ship classes are equivalent to W.O.I.N. ship classes.

Hull Data

• Double SS points.
• Convert dimensions and available cargo directly, and derive total cargo as normal (10 times the square of the ship's class).

Equipment Data

• Convert directly.
• If you are using the FASA starship construction rules, ELECTRONIC DEFENSE is is equal to double the Max Weapon Damage Factor (WDF), and CPU Cycles is equal to four times the Max WDF.
• Sensors are the same as the computer.

Other Data

• Convert directly.
• Multiply crew by 200 for monthly crew cost.

Engines And Power Data

• FTL speed is equal to FASA's Max Cruising Speed. 
• Subluminal SPEED is equal 20 divided by the FASA Movement Point Ratio value (the number before the slash, so for an MPR of 4/1 it's 20 divided by 4).
• Set fuel efficiency to 1.
• Operational range is calculated as normal (cube of the ship's class).

Weapons And Firing Data

• Ranges, arcs, and number  of weapons all stay the same.
• The attack bonus is shown in the table below.
• A beam weapon's damage is based on the FASA max power value; divide by 4, round up, for d6s.
• For missile weapons do the same, simlpy using the missile damage.

Shields Data

• SOAK is equal to half of FASA's maximum shield power; round up.
• Assume 4 shields.

Alternatively, the ship can be built from the ground up using equivalent components (or as close as possible):

Enterprise Class XI Cruiser

The Enterprise class cruiser is the refit of the earlier Constitution class cruiser USS Enterprise, the only surviving Constitution class cruiser of the original 13 constructed. These vessels began production thereafter at the Sol III shipyards.

This conversion of the FASA ship is relatvely accurate, and was accomplished by building from the ground up and uing equivalent or similar components.  The main differences are that the crew requirement comes out a little different (332 vs 412), but the 332 is the requirement - there's nothing to stop the ship having a complement of 412.  The weapons, shields, and engines all worked out fairly closely. In order to get luxury and various components (shuttlebays, transporters, etc.) up to standard, cargo space was lost, leaving this conversion with a cargo capacity of only 1500 tons (compared to the FASA ship's 22,500) but the FASA system did not incorporate facilities into the design process.