What PBM Tool does is to simplify the use of PBM, by popping up a intutioton 
interface which lets you click your way  instead of using the cli. It's 
created using MUI which mens it's very user friendly. To convert a picture
to an other format all you have to do is to select the picture from an
standard asl file requester, chose the output format, and click go. Now just 
wait and you'll have your new picture. In most cases that is :-) It's also
very easy to add new formats, all you need is a PBM like program...

 PERMSSN    UID  GID    PACKED    SIZE  RATIO     CRC       STAMP          NAME
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drwxr-xr-x   399/64          0       0 ****** -lhd- 0000 May 30  1994 PBM-Tool/
-rw-r--r--   399/64        110     172  64.0% -lh5- 393f May 30  1994 PBM-Tool/Install
-rw-r--r--   399/64       7115   32172  22.1% -lh5- 27d9 May 30  1994 PBM-Tool/PBM
-rw-r--r--   399/64      10437   32427  32.2% -lh5- 300a May 30  1994 PBM-Tool/PBM-Tool.guide
-rw-r--r--   399/64        482     969  49.7% -lh5- 3e75 May 30  1994 PBM-Tool/ReadMe.mui
drwxr-xr-x   399/64          0       0 ****** -lhd- 0000 May 30  1994 PBM-Tool/env/
-rw-r--r--   399/64         24      24 100.0% -lh0- db52 May 30  1994 PBM-Tool/env/PBM Tool.prefs
-rw-r--r--   399/64       1056    3913  27.0% -lh5- 43ca May 30  1994 PBM-Tool/env/PBM-Tool.config
-rw-r--r--   399/64         52     160  32.5% -lh5- 3281 May 30  1994 PBM-Tool/env/PBM.1.wini
-rw-r--r--   399/64       7102   40760  17.4% -lh5- 3a80 May 30  1994 PBM-Tool/pbm.e
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 Total        10 files   26378  110597  23.9%            Jun  2  1994