Yes, the cover somewhat annoys me too.
Maggot Brain is Funkadelic's third album and their most well known as it, arguably, was the album that started the funk/soul sound of the 70's. The title track, which opens the album, is nothing more than a 10+ minute guitar solo and, frankly speaking is probably the best piece of single guitar work I've ever heard (discounting Feedbacker, of course). It's somewhat akin to the solo in Pink Floyd's Shine on You Crazy Diamond, but drenched with emotion comparatively. Even if you can't be stuffed listening to the rest of the album, then you owe it to yourself to hear this piece of music, it really is an amazing feat.
The next few songs on the album are somewhat more 'standard', being shorter and containing vocals. I find it interesting that this album helped create the funk/soul sound but, really, is so much more than just funk and soul; it explores and transcends genres, but without sounding strange or pretentious. The last track, Wars of Armageddon, is essentially a giant jam session; it's great fun to listen to and caps off the album of nicely. A true classic of the 70's that still holds up today.
Very Close Runner-up AotW: Can - Tago Mago (it's been a rather 70's week)