I have:
1 from the 60's (Hot Line)
1 from the 70's (Jet Spin)
1 from the 80's (Night Moves)
2 from the 90's (TOTAN & Baywatch)
1 from the 2010's (Queen - it counts!)
If I had more space, I'd love to get one game each from the 30's, 40's, 50's and 2000's to round it out. Plus room for a 2020's machine in the future.