This week's favorite product is the Fisher Price Fun 2 Imagine Shopping Cart
After seeing how much my daughter loved the shopping cart toy at her PT appointments, I went out and got this one for her. She absolutely loves it. She can put things inside the basket, push it around on her knees and use it as a walker (with help). If your preemie is starting to get the idea of walking - or just wants a fun shopping cart toy - than I would highly recommend this one. The shelf on the bottom is perfect for adding a heavy object for increased stability (a 5 pound bag of sugar works nicely).
For beginning walkers you can use this as a makeshift walker. Just make sure you weigh it down or help hold on to it because it will tilt. If your preemie has equipment requirements, I have heard of parents buying old kid size shopping carts from places like Trader Joe's. They are a bit bigger and more stable for holding oxygen, monitors, etc.
Once your preemie is walking, you can encourage imaginative play by using the shopping cart for a game of grocery store. Get older siblings involved as well - they can be the checkout person or the bagger.
For school age preemies - you can encourage them to write out their own grocery list before shopping. This helps them work on writing as well as remembering what foods they can "buy." Make your own grocery list and have your preemie practice reading the list as you shop. This is also a great activity to do in a real grocery store.