How do you create a single 'skin' from multiples?

If I have an object that has, for example, 50 individual textures/materials; how can I convert them all to a single skin?

I believe doing this will give me performance increases. Anyone know of any drawbacks in doing this or not doing this?

I was wondering if leaving them as they are is easier for the graphics card rendering/memory as most of these individual textures are shared on many models, thus does making them into 1 skin per object become pointless?

I have things like Deep Exploration, Milkshape and Ultimate Unwrap on stand-by.

You need a texture packer, ask Gabriel (oops I mean Sybixsus) nicely (glimmergames) and he might sell you a copy.