source= http://www.piclist.com/postbot.asp?id=piclist\2002\08\09\013248a

ANTI-PROGRAMMER:
I can see where Byron is coming from... rather than making a beginners life
easier by teaching him how to program a chip faster or offering YET ANOTHER
alternative to programming a chip, just skip the programming issues entirely
and move on to getting something interesting, instructive and possibly
useful into and running on a PIC with some IO junk ready to go.

Later, if you want to add a ZIF socket on a Daughter Board (or a SMT socket
for that matter) and download a programmer application into the main PIC,
great.

Or maybe you want to add a stepper controller board and hook the thing up to
a physical device that needs to be moved about.

Or... whatever... the point is: Make getting working code into the PIC a
NON-ISSUE. Concentrate on teaching people how to do things with code in the
PIC and some simple hardware.


INTERFACE:
The interface to the host is always going to be a pain. As pointed out by
many, every path leads to failure in some subset of the possible cases. I
think there is only one solution: Redundancy.

- Parallel: Start with a standard parallel port interface via an 8 bit port
on the PIC and 3 control lines from another port

- USB 2 Parallel adapter: Really simple USB adapter chips that put out
parallel are a few dollars if that.
http://www.gigatechnology.com/usbmodprod.html
http://www.ftdichip.com/FTDriver.htm
Use this to build a Daughter Board that adapts USB to parallel and removes
the variations found between PC parallel ports. Win/*nix/Mac Drivers are
already written. Other people are doing similar:
http://baserv.uci.kun.nl/~smientki/PIC/PicProg/PicProgrammer_hardware.htm

- Serial: Include a minimal TTL-RS232 adapter (resistors and zenor diode)
http://www.piclist.com/io/serial/ttl-rs232.htm
(see Peter L. Perez's comments near the bottom)
and include a header for Ashley's RCL-1 TTL to RS232 adapter
http://www.piclist.com/io/serial/RCL1.htm
so that if you can't get a good serial connection with out the max232 on
board, it will be easy to add.

EXPANSION:
- DON'T GET HUNG UP ON ADDING EVERYTHING RIGHT NOW
- Make the system modular with a good connector (header) that will allow you
to add (even daisy chain) other devices later

Hey... that sounds sort of like... CUMP

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