WAD Concatenater v0.6 - By Matthew Ayres (author of WADED)

  Merge WADs with this small little utility.  Ever create a bunch of maps
  and wish you could save them all in one .WAD file?  Also capable of
  renumbering episodes and maps.  Version 0.6 works with Doom 1, Doom 2,
  and Heretic WADs.

  Since WADED had no ability to save multiple maps in a WAD, I created this
  little utility (in about 1 hour).  My original intention was to support
  this concept in WADED, however I knew it would be easier to create a small
  utility like this much faster.  People have been asking for this feature 
  for some time now.  I'm not even sure now if I'll include this feature in
  WADED, since it's probably easier just to use this utility.

  Using this utility is quite simple.  Run it and follow the instructions.
  Even if all the single map WADs you created were saved as E1M1, you can 
  renumber them as WADCAT creates the multi-map output file.

  WADCAT is FreeWare.  All I ask is that you use WADED, and register it
  if you like it.  :)  For more support, call the Lithium BBS (510-455-0425).