PFUNK, and Seymour...
Well you need to do a chip race. Works like this in a nutshell:
Everybody with a left over chip gets a card. All the chips are combined to form the next larger denom (meaning 4- 25's = 1- 100) the guy with the highest card by rank then by suit gets to keep it.
Here's an example:
Player A: 1- T25, Player B: 1- T25, Player C: 2- T25
Deal cards- Player A:

Player B:

Player C:
Black T100 goes to Player A because he has the highest rank card.
***Edit*** because I ran short on time this AM!!
If you have enough chips to form 2 higher denoms then the highest rank card gets the first chip and the second highest rank gets the second chip. 1 player can only earn 1 chip no matter what the rank of his other cards.
Also if 2 players get the same rank card it is decided by suit here's an example:
Player A: gets

Player B gets
Player B get this chip because the suits are Spades, Hearts, Diamonds, Clubs (or Clubs-Diamonds I will need to check).
May not seem entirely fair at first but the alternative is that you give everyone a black chip. Both and A and B would get T75 in chips when C only gets T50.
Theoretically the guy with the most cards has the greatest chance of winning the race, but it doesn't always happen like that.
Hope that helps some.