Neon is cool. It becomes metallic at unfathomably high pressures.
Silicon is cool because it’s a metalloid and it looks like aluminum foil.
Tellurium is cool because it’s odd like Silicon. It’s neither a metal nor a non-metal, but in between (but decently metallic for a metalloid). I think it used to be minted into coins?
Finally, mercury is unreactive. Obviously toxic but that’s not why I want to be Mercury. It’s semi-noble according to Wikipedia because it doesn’t really react with most acids and IIRC it doesn’t oxidise in air.