Example of address obfuscation:

1. I give a virtual address to my contact:
Contact's address: blackhole@xemaps.com
Virtual address: mega.byte@xemaps.com
Hidden address: my-real-address@yahoo.com

2. Contact sends message via virtual address:
blackhole@xemaps.com   >>   mega.byte@xemaps.com   >>   my-real-address@yahoo.com

Spamex also creates a surrogate address -- 7ngf-6qvo@xemaps.com -- for blackhole@xemaps.com

3. I reply using the surrogate address:
blackhole@xemaps.com   <<   mega.byte@xemaps.com   <<   7ngf-6qvo@xemaps.com   <<   my-real-address@yahoo.com

Result:
The contact -- blackhole@xemaps.com -- never sees my-real-address@yahoo.com. My address always appears to be mega.byte@xemaps.com.

Links to Spamex examples:

http://www.spamex.com/tool/aliasinfo.cfm?v=3632914 -- htcc-contact@xemaps.com (heavily spammed example -- history, contacts -- OFF)

http://www.spamex.com/tool/showhistory.cfm?v=9267498 -- mega.byte@xemaps.com

http://www.spamex.com/tool/aliasinfo.cfm?v=1336261 -- himself@xemaps.com (spammed -- history, contacts -- whitelist)

Useful links:

http://email.about.com/cs/dispaddrrevs/tp/disposable.htm -- top 10 disposable address services [About.com]

http://us.f308.mail.yahoo.com/ym/dea?YY=78791&y5beta=yes&y5beta=yes -- my Yahoo! Address Guard

http://billing.mail.yahoo.com/bm/Upgrades -- Yahoo! upgrades

http://antispam.yahoo.com/tools?tool=3 -- Yahoo! disposable addresses

Notes:

Adjective: Virtual -- Existing in essence or effect though not in actual fact.

workshop@cybercoyote.org is forwarded to my Yahoo! account.