Check out the baby centers in both Disneyland and California Adventure. They're clean, quiet, and a great place to feed, change, or nurse baby. They also have a first aid kit and you can refill your water bottles with filtered water.
Want to trade a pin? Ask any cast member. They'd be happy to trade with you.
Check into the Mark Twain Riverboat ride and if you're the first to ask, you can go into the wheel house and might even get to pull the horn.
Ask if you can ride in front of the Monorail and Train as well. Be sure to check with the train conductor and get on at the Main Street Depot.
Looking for a cool place to rest your feet? Stop by the Main Street Cinema for a breather during the afternoon heat and enjoy some classic Disney cartoons.
The Grizzly River lockers in California Adventure are free for the first two hours of the park opening.
If you pop a balloon while you're in the park, just bring it to the vendor and they will give you a new one.
There is a 15 min grace period for Fast Passes.
Fast Passes for World of Color are also located near Grizzly River Run. Fast Passes entitle you to a spot on the front side of the show which is essential. Pick up picnic food to enjoy while you wait for it to begin.
Looking for free filtered water? My favorite place is the Baby Center. But it's also been rumored that you can find filtered water in the following locations:
*The French Market in New Orleans Square
*Rancho del Zocalo in Frontierland
*Tomorrowland Terrace to the left of the order window in Tomorrowland
*Linked to these Parties