There are lots of options...
These offer the most authentic experience, and some people enjoy the collecting side. The downside is that they tend to look terrible on modern TVs, so ideally you would want a CRT. Of course you don't have that problem with handheld consoles like the Game Boy though. Buying original versions of games can be super expensive, but you can also get unofficial carts with 100+ games on.
Official Mini Consoles
The likes of Sega, Sony, and Nintendo have released mini versions of their most popular consoles over recent years. These ha