The following people have put resources into improving packet drivers.
Order of listing is more or less chronological.

John Romkey <romkey@asylum.sf.ca.usa>, who created the spec in the first place.
James van Bokkelen <jbvb@vax.ftp.com>, who is maintaining the spec.
Karl Auerbach <No longer at TRW>, who adapted MIT's PC/IP to use the packet
	driver spec and wrote a packet driver for the TRW-2000.
Phil Karn <karn@ucsd.edu>, who added a packet driver interface to
	his code, and supplied C code for the 3c501 and SLIP8250 drivers.
Bill Doster <Bill_Doster@um.cc.umich.edu>, who wrote a NI5010 driver in C for
	Phil Karn's net.
Russell Nelson <nelson@clutx.clarkson.edu>, who created the packet driver
	skeleton and adapted several existing drivers to it.
Bob Clements <clements@bbn.com>, who wrote the WD8003E and 3c503 drivers.
Brad Clements <bkc@omnigate.clarkson.edu>, who adapted NCSA Telnet to use the
	packet driver spec.
(Bob and Brad are not related.)
The Wollongong Group, in the person of Leo J. McLaughlin <No longer at TWG>,
	which has committed to supporting the spec.
3Com, in the person of <Eric_Siegel@dsd.3mail.3com.com>, has been helpful
	in getting 3Com's documention to packet driver authors.
Dan Lanciani <ddl@harvard.edu>, who wrote the 3c523 driver.
Denis DeLaRoca <delaroca@denis.oac.ucla.edu>, who added hardware handshake
	to the SLIP8250 driver.
John Grover <JGROVER@maine.bitnet>, who optimized the SLIP8250 driver to
	work at 38.4 Kbps.
Rainer Toebbicke <RTB@CERNVM.bitnet> who wrote the BICC Isolan driver.
Jan Engvald LDC <xjeldc@gemini.ldc.lu.se>, who improved the wd8003e driver,
	and added MicroChannel support.
Krishnan Gopalan <gkrishn@eng.clemson.edu> and
Gregg Stefancik <wstef@eng.clemson.edu> of Clemson University Engineering
	Computer Operations, who wrote the packet driver for the 3c505 card.
Vance Morrison <morrison@acns.nwu.edu> added starlan support to the wd8003e
	driver.
Brian Fisher <fisherb@qucdn.queensu.ca>, who wrote an "Ethernet" packet driver
	for the IBM Token Ring Adapter card.
Eric Henderson <eric@dcsprod.byu.edu> of Brigham Young University, who wrote
	a packet driver for Novell's NE1000 and NE2000.
Joe Doupnik <jrd@cc.usu.edu> improved head.asm by adding some comments and
	brought it further into line with the PDS, added promiscuous mode to
	the wd8003e driver, and modified the PC/IP netwatch to use packet
	drivers.
David Horne <71271.1141@CompuServe.COM>, who wrote a packet driver for Novell's
	NE2000.
Michael Haberler <mah@wu-wien.ac.at>, who wrote an IP over NetBIOS packet
	driver.
Paul Kranenburg <rulcs!kranenbu@relay.eu.net>, who wrote an IP over IPX packet
	driver.
David E. Johnson <dave@tacky.cs.olemiss.edu>, who fixed the 3c505 driver.
James A. Harvey <IJAH400@indyvax.iupui.edu>, who fixed the AT test in tail.asm
	and the 3c503 lockup problem.
Anto Prijosoesilo <anto@anto.acs.unt.edu>, who fixed a bug related to DMA in
	the ni6510 driver.
John Mann <johnm@vaxc.cc.monash.edu.au>, who submitted some code to delay the
	etopen and convert between Novell's pseudo IEEE 802.3 packets and
	Ethernet packets.
Drew Daniel Perkins <ddp+@andrew.cmu.edu>, who designed and implemented
	as_send_pkt (asynchronous send) for the wd8013ebt, and improved
	pktsend in the process
Katie Stevens <kstevens@ucdavis.edu>, who wrote a LocalTalk driver.
Steven Wallace <wallaces@ucs.indiana.edu>, who added a hack for MS-Windows.
Reinhard Strebler <RZ40@DKAUNI2.BITNET>, who hacked on termin, and slip8250.
Martin Knoblauch <XBR2D96D@DDATHD21.BITNET>, who fixed ni5010 promiscuous mode.
Tobias Reber <dok235@cvx12.inet.dkfz-heidelberg.de>, who fixed the 3c523.
Gregory T Small <gts@violet.Berkeley.EDU>, who found a bug in the packet
	interrupt verification.
Dave Price <dapx@cs.aber.ac.uk> wrote a packet driver for the Mitel
	Express ISDN card.
Doug Smith <smithdg@clutx.clarkson.edu> ported the ni6510 driver to the
	depca card.
Don Provan <donp@xlnvax.novell.com> fixed a bug in the -n switch code.
John Baird <J.Baird@tahi.lincoln.ac.nz> wrote some ipxpkt documentation.
Sylvan Butler <sbutl@bert.cs.byu.edu> fixed two bugs in ubnicpc.
Markku Toijala <mto@xerver.icl.fi> who submitted a packet driver for
	the ICL EtherTeam16 (formerly Nokia Data), and some fixes for
	IBMTOKEN.
Chris Elmquist, <elmquist@SSESCO.com>, who modified the Tiara packet driver
	to work on the Multitech EN301.