Germany, Liechtenstein, Denmark, Sweden, Russia, Norway, Netherlands, Belgium, USA, United Kingdom (only England), Luxembourg, France, Spain, Italy, Switzerland, Austria, Vatican City, Croatia, Bosnia and Herzegovina, Namibia, South Africa, Tanzania, Slovenia, Slovakia, Poland, Czech Republic, Hungary, Cuba, Jamaica, Estonia, Thailand, Dominican Republic
And Canary Islands but that counts as Spain.
When you live in the middle of Europe you almost automatically see a lot of countries if you travel a bit.
I definitely want to see in the future:
Australia, New Zealand, Brazil, Costa Rica, Canada, Japan, China, Vietnam