Abstract of INFO-MAC archived encoded Mac binary file
   'comm/inet/mail/yahoo-mailto-handler-12.hqx'
  Uploaded 10/03/2002   89640 bytes

From: "Daniel A. Shockley" <yahoomailtohandler@danshockley.com>
Subject: Yahoo Mailto Handler 1.2


New in version 1.2 full
-- contains both a Mac OS Classic and Mac OS X applet. You'll need 
CarbonLib for it to run in Classic.

This little AppleScript applet can be used to handle mailto URLs. So, 
when you click on an email address on a web page, it goes to the 
Yahoo web mail Send Message page, with the email address filled in. 
If there are other parts, they will also be filled in (subject, cc, 
bcc, body, and perhaps other)

You will need to open the Internet control panel and select this as 
your Email Application at the bottom of the Email tab.

I plan on extending it to work with other major webmail sites, as 
long as they support sending mail by adding text to a URL. Let me 
know if you'd like to work on it. Most useful utilities out there 
only help people who use stand-alone POP/SMTP clients, not us 
web-mail users.

I got some information that was helpful about this from:

Kirk Klingbiel - the "open location" part of AppleScript

Cory S. Moll - the webPath for Yahoo that works independently of 
which us.f**.mail.yahoo.com server you are on