Wouldn't that be two? The bike and the trainer. But if it's a legit answer I'd go with that. Otherwise, just the bike.
A big hill. Seriously. A long walk up a hill is one of the best workouts and jogging up is a real killer, especially for a Clydesdale like me.
A Total Gym. It really does what they say, you don't need a spotter, and it's great if you don't have a lot of room to dedicate to workout equipment.
Who? No clue who that is. I have used them for over 20 years. You do not need all the expensive junk to get a full body work out. For cardio all you need is a pair of shoes you can run in, some shadow boxing, jumping jacks.