De Bellis Vietnam is a set of DBA-based quick and dirty rules for wargaming Vietnam.
De Bellis Toyus is a set of rules for using kid’s toys for wargames. The rules are loosely based on Phil Barker’s DBA.
The Bookranger offers a set of free wargames rules for Napoleonics using DBA mechanisms. The author writes:
These rules derive from the combined concepts put forward in the rules sets “De Bellis Antiquitatis” and “Chef de Battalion”.
It was envisioned that a player is likely to control a single Battalion within these rules (a battalion having 15 bases or more). However it is possible to play these rules with a single battalion represented by a single base, when playing large scale battles.
The Solitary Wargamer offers a variant of DBA for the English Civil War.