I like the Knight because it is so versitile.
What's your favorite chess piece?
Umm... Sorry to crash the party but I saw a thread just like this several days ago.
Posting in an old thread is always better then making a new one, that applies to basically every forum on the internet. Use the search box in the top right to find old threads. Once you make a post the thread will appear in front of the forum and recent posts page as long as people keep posting. Delete this thread by deleting your first post and have fun with forums newbie!
Though I somewhat agree with NM-or-bust's comment, Chess.com has a particularly large pool of threads and a particularly inaccurate search tool. As there are a relatively small number of discussable topics in the realm of chess, threads tend to go on for pages and pages, making them harder to navigate than multiple common issue threads. That said, I'll answer the original post.
I like the king. He's a much more useful piece than many people give him credit for, and I've won quite a few theoretically drawn positions(as well as a handful of those which were theoretically lost) by simply having the better understanding of how to use him.
Different people like different chess pieces for different reasons. Some may like kings because they're the most important. Some may like queens because they're the most powerful. Others may like pawns because they're the cutest and most innocent. What's your favorite?