The bundle with 2 DLC characters is also on sale for $4.99.
Cult favorite status (uh maybe Skullgirls is coming to the PC in August - thanks to a successful Indiegogo campaign where the developers raised over $828,000 to port the game over. Everywhere else has the game at full price of $15 but Gamefly has preorder of Skullgirls for only $11.99 after coupon. You also get beta access to the game which starts August 1st. Kinda sad for those that have "preorder" even earlier through Indiegogo - which cost as much as $36 for the Steam key (granted you get a bit more goodies such as the OST and wallpaper pack).
$14.99$7.50at Green Man Gaming
$14.99$7.49at Best Buy
$499.99at Best Buy