If it ever gets delivered.

Install cgminer

ACCEPT_KEYWORDS="~amd64" USE="bflsc" emerge -av net-misc/cgminer
[ebuild  N     ] dev-libs/jansson-2.5  USE="-doc -static-libs" 399 kB
[ebuild  N     ] net-misc/cgminer-3.6.4  USE="-adl -avalon bflsc -bitforce -doc -examples -hardened -icarus -klondike -modminer ncurses -opencl -scrypt" 2,330 kB

Connect the ButterflyLabs Device

Connect it's power, then connect the USB

[760216.560011] usb 1-1: new high-speed USB device number 3 using ehci-pci
Use the Eligius Pool bfgminer \ --url mining.eligius.st:8337 \ --userpass <Your Bitcoin Address> \ --api-network
cgminer \
    --url http://mining.eligius.st:8337 \
    --user 1P4MBgFP46mByiswyu3cg4qYZ3xRE8ooT \
    --pass x \
cd /usr/src
git clone https://github.com/ckolivas/cgminer.git
cd cgminer
./autogen.sh
CFLAGS="-O2 -Wall -march=native" ./configure --enable-bflsc