The Needle's Eye that Jesus spoke of was actually a place. It was a
mountain passage through which most merchants/traders had to pass if they were moving along the major
trade routes. It was an extremely small path, and was very difficult to go through if you had a camel with you loaded with goods. Basically, the merchant would have to unload the camel, bring his belongings through piece by piece, and then go back and get his
camel. Made it very difficult, but not impossible.
Saturday Night Live does a skit on this in which a wealthy person attempts to melt camels and force them through overly-sized eyes of needles. Quite humorous.