BFGMiner is a modular ASIC/FPGA miner written in C, featuring dynamic clocking, monitoring, and remote interface capabilities.

BFGMiner features:

A large variety of device drivers for Bitcoin (SHA256d)
CPU and OpenCL/GPU mining for Keccak (SHA-3)
Automatically can configure itself to failover to solo mining and local block submission when Bitcoin Core is running
Support for getblocktemplate decentralized mining protocol (no proxy needed!)
Built-in stratum and getwork proxy server
Very low overhead free C code for Linux and Windows with very low CPU usage
Integrated overclocking and fan control (including automatic adjustment, if configured)
Heavily threaded code hands out work retrieval and work submission to separate threads to not hinder devices working
Caching of submissions during transient network outages
Preemptive generation of work prior to completion of current work
Automatically detects failing pools and disables them
Multi-device support (all or discrete selection)
Much more.