Bulfinch's Mythology

Bulfinch's Mythology is a terrific book. There are many great Roman myths (including 20 page summaries of both the Illiad and the Odyssey ).

My personal favorite would have to be from the end of the book, however, when it gave a few Egyptian and Norse myths.

Thor, Loki (the gods of thunder and trickery, respectively), and one of their sevants were in the forest one day when they happened upon the city of the giants one day. They were invited into the hall, and told that all giants must prove themselves worthy. They excepted the challenge. Loki says that he can eat faster than any man alive, and so is put in front of a trough filled with meat; the giant Logi on the opposite side. They both set to eating, and meet in the middle. Logi has eaten everything, including bone and trough, while Loki only ate the flesh, and so in declared winner. The servant says he can run faster than anyone. The giant facing him laps him three times. Thor insists he can drink more than anyone. The horn in front of him is hardly diminished after three huge draughts. He also says he has enormous strength. When a huge cat is put in front of him (which the giants say they can all easily lift), he only manages to lift one paw. He then challenges the giants to a wrestling match. They send a crone, and Thor loses after several minutes.

On their way out of the city, the leader of the giants reveals that he has deceived them through illusions. Logi was truly all-consuming Fire, the running giant truly Thought (which no man can outrun), the horn was connected to the ocean, the cat the world-serpent Jormungandr (the giants were terrified to see him lift it at all), and the crone Time (who will defeat everyone in the end). When Thor turns to kill the giant and destroy the city for his shame, they are both gone, him seeing nothing but an empty plain.

I overwhelmingly prefer Norse mythology, personally, although there was much, much less of it than Greek or Roman.