Presented 1994, Blowfish is still not brocken, is still one of the powerfull encryption algorithms and was the first strong one free of patents and with a free copyright.
Twofish was one of five finalists of Advanced Encryption Standard selection. It is very powerfull and... it is free of patents and with a free copyright.
On Sep. 02, 2000 Rijndael was officially selected as Advanced Encryption Standard algorithm by NIST (National Institute of Standards and Technology). Here a part of NIST's AES report with a short history of the selection:
On January 2, 1997, NIST announced the initiation of an effort to develop the AES  and made a formal call for algorithms on September 12, 1997 . The call indicated NIST’s goal that the AES would specify an unclassified, publicly disclosed encryption algorithm, available royalty-free, worldwide. At a minimum, the algorithm would have to implement symmetric key cryptography as a block cipher and support a block size of 128 bits and key sizes of 128, 192, and 256 bits. On August 20, 1998, NIST announced fifteen AES candidate algorithms at the First AES Candidate Conference (AES1) and solicited public comments on the candidates . Industry and academia submitters from twelve countries proposed the fifteen algorithms. A Second AES Candidate Conference (AES2) was held in March 1999 to discuss the results of the analysis that was conducted by the international cryptographic community on the candidate algorithms. In August 1999, NIST announced its selection of five finalist algorithms from the fifteen candidates. The selected algorithms were MARS, RC6TM, Rijndael, Serpent and Twofish.
Copyright © 2009. This Object (page with whole content) is open source and can be modifyed and/or copyed unter der terms and conditions of the Universal General Public License (UGPL). This statement does not apply to the UGPL, the copyright statement of this site itself and the logo (top left image on each page). The logo image may be copyed with the page itself, but changing it is not allowed. All other rights on this image are reserved too.