Round circus-style playhouse. I like the hanging flower pots with removable daisies. A tent-top or A-frame playhouse makes the most sense to me, because it gives some extra room for bigger kids. The card table flat-top playhouses look pretty small inside.
Play house from cardboard box!!! I hope I'm a creative enough mom to do this for my kids someday.
PVC playhouse, just add sheets! My dad made this for my one year old daughter as a Christmas present, and it has been up in our living room ever since! I purchased some pink and white sheets at Walmart and strung some Christmas lights around the top! We have our snack in there everyday, and it's home to all her favorite stuffed animals. LOVE THIS!