First of all, we bought a new stroller that would accomodate her cast. What you want to look for is a smaller stroller that has a shallow seat and will accomodate spread legs. However, you will learn that while something may accomodate one cast the next cast may require a little tweaking. With Kennedy's second cast her legs were a little wider spread so we stuffed a pillow into the back to push her further foward and then seat belted her in to keep her there. We kept the pillow there with Kennedy's third cast because the cast had more of a reclined position so the pillow kept her in a better strollering position. This stroller has proven to be invaluable and is well used. Kennedy always finds strollering outside to be fun and a great distraction so it has gotten us through a lot of rough days.
We also use two bean bag chairs, one in the bedroom area and the other in the living area, so I don't have to lug one around while carrying Kennedy. This is a great way to put Kennedy down with a toy so I can get a few things done (shower, eat, go to the bathroom...). In the beginning I would pull the bean bag chair up to a low coffee table so she could have some toys on the table and play. That was great although it was easy for her to slide from a sitting position to a reclining position and the toys fell off the table easily. Overall, the bean bag chairs are great and also invaluable for day-to-day living. I also used Kennedy's old bouncy chair from time-to-time although it didn't handle her weight well - I think she was just too big for it!
Probably the best purchase is our watermelon Ivyrose spica chair. We received our about 6 wks into our spica experience, with 9 wks to go. After 2 days with the chair I didn't know how we'd survived w/out it. The chair is built and designed by a mom with two spica girls and made to fit a variety of cast positions. I know the creator of Ivyrose spica chairs is undergoing some business changes involving upcoming federal laws so I'm unsure of the availability of her chairs but I highly recommend visiting her website and looking into getting one of her chairs to help you through this experience. Her website is: http://www.freewebs.com/arymanth.
Here are some items other people recommend:
strollers: umbrella strollers, Bugaboo Frog stroller, Mia Moda Cielo stroller,
BabyTrend Expedition LX jogging stroller
baby carriers: Mei Tai carriers, Ergo baby carriers, Hippychick hip seats
ride on toys - cars, trains - for spica casts without the stability bar
You can also visit www.CuteLittleChurch.com/JoysHip and http://www.hip-baby.org/ for more ideas regarding how to entertain your child while in their spica cast!