joinduet.com is a site to upload and share your software serial numbers and keys. It may become useful when you want to test some software but you do not want to pay bore you made a decision to use it for a long time. Using the site you can easily unlock any software. After you decide that some application is really useful for you you MUST purchase an activation key.
This site is not a commercial project. It is run and maintained by a free software fan. Site has been created not for profit but to give a possibility to share serials you own with other users.