For Christianity:

Arianism - Founded by Egyptian bishop Arius. Doctrine of Jesus not being God since he was created. Denied belief in trinity, therefore extremely heretical. Spread among Germanic tribes but wiped out by 6th century.

Coptic Church - Jesus was only of one nature, completely God, not a man. Also extremely heretical, located in Egypt.

Docetism - very early Christian group, deeply influenced by Gnostics. Jesus was a disguise used by God while he was with man. Jesus's sufferings were illusionary, and he was not even nailed to the cross, it was an illusion/someone else took his place. Crushed by 4th century.

Donantism - not really a heritical sect, as the reaffirmed trinity doctrine, but they refused to acknowledge Rome's leadership. In North Africa, crushed in 412 though the belief lingered on.

Montanism - founded by Montanus around 170, spread through Turkey. God spoke directly through leaders and women were allowed higher positions in church. Lost popularity quickly...

Nestorianism - Nestorius of Syria (died 450) Jesus was made up of two persons one human, one divine. Mary was only the mother of the human Christ, not God. Fled towards Sassinan lands.

You know Mormons and Jehovas Witnesses but those are latter groups...

Also the Eastern Orthodox and Roman Catholic churches both excommunicated each other around the 11th century.

And of course the Lutheran/Calvinist/Anabaptist movements...

Islam:

Shi'ites, Kharjites, Mutazalites, Ismailis, though I don't know the official position as Islam is very wary of rendering one apostate, and with the exception of probably Ismailis, the others are conserided deviants, not apostates.