XDCC Catcher is the most advanced download manager for XDCC bots. Its been under development since 2009, has more than 32000 lines of pure code and is available in a free Basic version and a paid (15 euro) Pro version.

Some of the features are :

• Connect to 100s of networks and join 1000s of channels
• Get 1000s of packets in your list
• Local queue: Automatic re-request after errors
• Local queue: Queue manager (Pause, Cancel, etc)
• Advanced search function (including regular expressions)
• Autoconnects and autojoins
• Extensive list of settings: from General to DNS servers
• Socks/Proxy support
• Private messages (send and receive)
• Modern, optimised windows interface
• Automatically check for updates
• Support for uPnP
• Join channel and chat
• XDCC list request interface (request XDCC list of bots)
• Bot score (number to compare bots)
• Rollback check (prevent corrupted downloads)
• Multiple network lists
• Restore (backup) queues
• Buildin HTTP server
• Advanced NickServ/identities support
• Auto-clear requests
• Internal web browser
• Recent finished files list
• Reconnect on (not forced) disconnect
• Report/block trap- and closed channels

If you're unfamiliar with IRC and/or XDCC, please read the chapter "Brief introduction to IRC and XDCC" in the XDCC Catcher Basic quick start.