This trade is terrible and no team would do it other than the Celtics. They clearly win on this, its not even close.
Look at the Lakers roster - 90% of it is 1 year deals, the exceptions Nash and Kobe. Nash will be an expiring next season. The Lakers are trying to rebuild for next season and draw in another star or 2 to play along with Kobe for the next 2 years. They're not going to ruin that opportunity for Lin and Wallace, they provide no talent and terrible contracts.
I doubt the Pacers would have any interest. They're fine where they are right now #1. They're trading a better player for 2 lesser players. And they already have a deep team so adding 2 role players for a major scoring threat when healthy does not make sense for them.
Lastly Houston. They're looking for a small PF to put next to Howard. Gasol is not that. Gasol would be a half season rental as they can't afford to resign him next year. Why give up Lin and Asik for a half year rental back up Center? Makes zero sense.
I'd love the trade for us. But will never happen. Get it out of your head.