Fun Friday: Puzzling Math

Let's make this a fun Friday. Here's a little brainteaser for budding mathematicians old and new.

Rules:

1.  Each letter represents the same digit.

2.  Once letters have been replaced with a digit, the "math" has to work.

3.  Once a digit has been used for a letter, that digit can't be used for any other letter.

Simple Sample:

     MY + HE = US

Possible Answer (there may be more than one right answer):

     M=1, Y=2, H=7, E=8, U=9, S=0

     12 + 78 = 90

Now you try this one:

   PIG + PIG = OINK

There may be more than one right answer for this one as well. Give it a try and let me know what you come up with.