Going to Bali, we have a 10 hour (AM to PM) lay over in Los Angeles (what to do for 10 hours), on the return we have an 8 hour layover in Singapore (PM to AM) now what to do for 8 hours. Please don't tell me to find a new flight.
Have not been at either airport for any lenght of time, anyting to do there or nearby. thanks

If you're going to be in Singapore during the evening... you must go to the Night Zoo! I belive it may be one of the only zoos in the world that is open at night so you can see the animals in their own habitat, interacting with each other, etc.
Have a great trip.

In LA, if you can leave your carry on luggage at the airport, take a cab/shuttle into Manhattan Beach (should not be more than $15 and 15 minutes to get there) South of the Airport. It is a very nice seaside community with restaurants, shops and a beach walkway (the Strand). Nice inexpensive restaurant is Mama D's Italian
http://www.seetheglobe.com/modules/w...p?cid=6&lid=62

After Manhattan Beach, head South to Hermosa Beach on the Strand (30 minute walk) and enjoy some SoCal weather. Have lunch at Chef Melba

http://www.seetheglobe.com/modules/w...?cid=6&lid=353

and coffee at the Coffee Bean and Tea Leaf.

If you have time head another 30 minutes south to Redondo Pier.

Take a cab back to LAX 2-3 hours prior to your flight.

But how is the OP going to leave their carry-on baggage at LAX? No US airport has baggage lockers any more.

Just schlepp the carry-ons with you.

If you type in LAX Layover in the search area, you'll find lots of ideas such as Santa Monica, The Getty, etc.