Twitter Groups allows you to tag your followers into different groups. Then you can send a message to those groups without needing to send the message to each person one at a time!
R. Jäschke, L. Marinho, A. Hotho, L. Schmidt-Thieme, and G. Stumme. Knowledge Discovery in Databases: PKDD 2007, 11th European Conference on Principles and Practice of Knowledge Discovery in Databases, Warsaw, Poland, September 17-21, 2007, Proceedings, volume 4702 of Lecture Notes in Computer Science, page 506-514. Springer, (2007)
M. Grahl, A. Hotho, and G. Stumme. 7th International Conference on Knowledge Management (I-KNOW '07), page 356-364. Graz, Austria, Know-Center, (September 2007)
R. Jäschke, L. Balby Marinho, A. Hotho, L. Schmidt-Thieme, and G. Stumme. Knowledge Discovery in Databases: PKDD 2007, 11th European Conference on Principles and Practice of Knowledge Discovery in Databases, volume 4702 of Lecture Notes in Computer Science, page 506-514. Berlin, Heidelberg, Springer, (2007)
R. Jäschke, L. Marinho, A. Hotho, L. Schmidt-Thieme, and G. Stumme. Knowledge Discovery in Databases: PKDD 2007, 11th European Conference on Principles and Practice of Knowledge Discovery in Databases, Warsaw, Poland, September 17-21, 2007, Proceedings, volume 4702 of Lecture Notes in Computer Science, page 506-514. Springer, (2007)
R. Jäschke, L. Marinho, A. Hotho, L. Schmidt-Thieme, and G. Stumme. Workshop Proceedings of Lernen - Wissensentdeckung - Adaptivität (LWA 2007), page 13-20. Martin-Luther-Universität Halle-Wittenberg, (September 2007)
M. Grahl, A. Hotho, and G. Stumme. 7th International Conference on Knowledge Management (I-KNOW '07), page 356-364. Graz, Austria, Know-Center, (September 2007)
M. Grahl, A. Hotho, and G. Stumme. 7th International Conference on Knowledge Management (I-KNOW '07), page 356-364. Graz, Austria, Know-Center, (September 2007)
J. Voss. Open Innovation : Neue Perspektiven im Kontext von Information und Wissen Beiträge des 10. Internationalen Symposiums für Informationswissenschaft und der 13. Jahrestagung der IuK-Initiative Wissenschaft Köln, page 243--254. Köln, UVK Verlagsgesellschaft mbH, (Jan 26, 2007)
E. Michlmayr, and S. Cazer. Tagging and Metadata for Social Information Organization Workshop in conjunction with the 16th International World Wide Web Conference, (May 2007)
A. Rivadeneira, D. Gruen, M. Muller, and D. Millen. CHI '07: Proceedings of the SIGCHI conference on Human factors in computing systems, page 995--998. New York, NY, USA, ACM, (May 2007)
M. Grahl, A. Hotho, and G. Stumme. Workshop Proceedings of Lernen -- Wissensentdeckung -- Adaptivität (LWA 2007), page 50-54. Martin-Luther-Universität Halle-Wittenberg, (September 2007)