What's the difference between LITTLE and SMALL?

Vladislav Spector asked that question on our Let's Master English community.

Manoj gave the first great answer...

MANOJ pandeyApr 19, 2013

small = limited in size or amount when compared
little = small in size or amount
I'd rather live in a small town than a big city
it came in a little box

Then Gustavo offered a great link:

Gustavo A. Fernández BermejoApr 19, 2013

http://www.eslbase.com/grammar/small-little

And then I offered a few more examples:

All good answers and references...

BUT! My little brother refers to my younger brother and my smaller brother refers to my physically smaller brother--he could be younger or older!

I had a little cake. (could be an entire cake that wasn't very large OR just a tiny portion of a cake!)

I had a small piece of cake. (a tiny portion)

I exercise a little every day.
I exercise a small amount every day. (the same as above)

A little cold is okay, but not -10 degrees!
~~~SMALL~~~doesn't work

I'll have a little coffee. (not very much)

I'll have a small amount of coffee. (SAME as above)
I'll have a small coffee. (specific size (Small, Medium, Large))

Your head is small. (physically "under-sized")
You have a little head. (Same)

Give me a little hug. (affectionate...not too long)

Give me a small hug.  (not very affectionate, very short)

Can you think of more interesting examples?^^