Free snacks/drinks are always nice. Having lunch delivered also keeps people at their desk, working longer.
Edit - I used to work for a company that offered a daily lunch budget, on the condition that it be delivered. You were free to eat anywhere you wanted, but realistically, you stayed in/around the building.
In the event that you had to stay after-hours, you were alloted a dinner budget to order in with everyone that had to stay.
Also, we had fresh fruit delivered as needed and Monday/Wednesday/Friday, fresh bagels and pastries were delivered.
We worked our butts off, knowing we didn't have to go home and make dinner/do groceries.
This was over in Denmark...I've only worked for one company in North America with as awesome a setup.
Implementing any of the above would probably go a long way.