Sopwith Mods (1984 - 2003)
There have been numerous modifications made to the classic Sopwith game, some modifying the terrain, others altering the music, sound effects, and other miscellany.
The Red Baron [DOWNLOAD]
Essentially a modified version of Sopwith 1 with identical gameplay. Only the title screen, with the multiplayer feature option, has been altered. The question of who altered it and why is a mystery. Requires DosBox to play. Thanks to Seth Vinchattle for re-discovering this game!
Top Gun [DOWNLOAD]
A clone of Sopwith2 with altered title screen text by "Frank and Jeff" with comments about "Barry".
A modified version of Sopwith2 by "firstname.lastname@example.org" that alters the map, music, and text. It's very difficult to beat a level in Sökwith due to the tricky object placement. There is a hidden easter-egg in Sökwith where the outline of the map looks like a... well... you'll have to find out for yourself!
A modified version of Sopwith2 by "Samor" that replaces the landscape with rectangular shapes, and alters the music and text.
It's now easy to design your own Sopwith mods with two utilities:
Andrew Durdin's simple map editor written in Qbasic (you can read the instructions to run it here).
Matt Zebrowski's much more advanced level designer in Visual Basic that can import any Sopwith EXE file, make changes using a pen-tool, and export a recompiled Sopwith game with the new map.
And one more honorable mention:
Artman's Goplanes [DOWNLOAD]
Shawn LeBlanc's side-scrolling Sopwith-esque DOS game with colorful graphics and smooth gameplay. Requires DosBox to play.