Cingular Wireless is allowing its cell phone subscribers to exchange text messages with Yahoo instant messaging buddies, helping the Web giant extend its reach beyond the PC. The feature does not cost extra for Cingular subscribers, and it is free to Yahoo Messenger users, the company said Thursday. The No. 2 U.S. wireless carrier charges 10 cents a message, or $2.99 and $9.99 for 100 and 500 messages, respectively. Read more: CNet News.