Tried and true baby toys?

What are some of your tried and true developmental toys? We started off with the kick and play piano which has been wonderful for the first 3 months. I'm looking for something now that can sit her up and play. I saw a Fisher price 4 in 1 step and play piano, which has all the bells and whistles, but with a price tag of 130.00! I don't know if it's worth it or not? I've also priced the exersaucer for around 50.00 and looks pretty enjoyable for my little one. Thoughts? Suggestions??