Java was fun to play with back in the early days. It was fast, had a VM, garbage collection and was OO. Sadly the fun was gradually removed over the years as a result of design-by-committee and a desire to try to solve some of its core issues.
Fortunately you can still have fun on the JVM, even though I prefer to avoid it these days given its current custodians.
That said, I've already professed my love for the Go language, which I consider the spiritual successor of the C programming language.