Did Christianity borrow from ancient religions?

While reading the 18th chapter of Morals and Dogma, I noticed that Pike mentioned several ancient cultures that used the symbol of the cross for religious purposes before the Christians did. It reminded me of something that I read a while back about the similarities of Jesus and other ancient "pagan" deities. These ancient deities shared the same birth stories, messages of salvation, death and resurrection as Jesus. Some examples of these gods include: Osiris, Attis, Dionysus, Mithras and Krishna. I decided to revisit the the subject and did some quick searching on the internet.

Most of the sites listed on Google greatly exaggerated the connections between Christianity and older religions. These sites made it look like Christianity directly "stole" from these earlier religions.

Some of the other sites completely dismiss any connection at all. They claim that Christianity is unique and deny that it borrows anything from ancient religions.

I finally found a site that was really good at explaining the connection: Pagan Origins of the Christ Myth. It lays out all of the facts in a straightforward manner and lets the readers decide for themselves.