AsterSwitchboard is a well known Windows CTI client software for Asterisk, recently developed with all the features required by a modern operator panel such as: BLF, drag & drop, call log, contacts book, click to call, tel: and callto: link management, ecc…
Since few days a free version is also available, you can download it from here:
http://www.asterswitchboard.com/en/download.php
Best regards, Gianluca