Coininfo.com - http://www.coininfo.com/
Provides up to date information on spot prices, charts, and individual coin prices.
Collecting Colombia - http://www.freewebs.com/collectcolombia/
Dedicated to promoting collecting the classic stamps of Colombia.
County Stamp Center - http://www.stampcenter.com/
A stamp collecting dealer that provides stamp collection values, stamp collection appraisals and also sells new issue foreign stamps from countries around the world.
Icollectit - http://www.icollectit.co.uk/
Find all types of autographs, signed cards, autographed photos, autographed memorabilia and collectables.
International Federation of Postcard Dealers - http://www.playle.com/IFPD/
Organization for postcard collecting. Brings together different postcard dealers.
Postcardy - http://www.postcardy.com/
Explore the world of postcards. Learn all about postcards and postcard collecting.
PostSecret - http://www.postsecret.com/
An ongoing community art project where people mail in their secrets anonymously on one side of a postcard.