Untested code:
* QuickTime is untested: it may or may not work

Promising extractors that probably deserve to be written:

image:
* tiff

text:
* dvi (creation date, page count)
* man pages (title, modification date, authors, brief description)
* info pages

office:
[Note that for text-files, the language-specific printable extractor
 (-B en) works quite nicely.]
* rtf 
* Microsoft doc 
* StarOffice sdw
* Microsoft ppt
* Microsoft xls

video:
* mpeg
* avi

code:
* Java (@author, @version, classname, inner classes, brief class description)

packages:
* deb 



KNOWN BUGS:

1) On FreeBSD, running with -B en on the GPL:
Program received signal SIGSEGV, Segmentation fault.
0x0 in ?? ()
(gdb) ba
#0  0x0 in ?? ()
#1  0x2825e919 in __do_global_dtors_aux () from /tmp/grothoff/lib/libextractor_printable_en.so
#2  0x28261769 in _fini () from /tmp/grothoff/lib/libextractor_printable_en.so
#3  0x2804effe in dlclose () from /usr/libexec/ld-elf.so.1
#4  0x2806d8cd in sys_dl_close (loader_data=0x0, module=0x28066300) at ltdl.c:988
#5  0x2806fea7 in lt_dlclose (handle=0x8062780) at ltdl.c:3312
#6  0x28069544 in EXTRACTOR_removeLibrary (prev=0x8064300, library=0x804d580 "libextractor_printable_en") at extractor.c:529
#7  0x280695ac in EXTRACTOR_removeAll (libraries=0x80642f0) at extractor.c:549
#8  0x80495bc in main (argc=4, argv=0xbfbffbac) at extract.c:456
#9  0x8048ae1 in _start ()

