Plugin Alliance is giving away their Ampeg SVT-VR Classic plugin for free until February 19th. Use the code AMPEG-FOR-FREE to get it from their website.
If you're unfamiliar with the Ampeg SVT and it's various incarnations, it's probably the most-used bass amplifier of all time. If you look at live performances of all sorts of genres you'll probably find the bass player using an Ampeg amp, and more often than not it will be an SVT variant. Just like this video here: