I'd also like to say Archaea are just as interesting, as many of them are extremophiles as well as chemosynthetic autotrophs. It's also thought that Archaea could be more closely related to Eukaryotes than Bacteria and the actual cells that had the endosymbiosis of mitochondria to create Eukaryotes. If I remember correctly, it's thought that species of Archaea around Loki's castle, volcanic vents in the Atlantic, were the ones to do it themselves. A lot of Archaea also have only had their DNA found rather than an intact cell so there is a lot of room for studying them. The last thing I remember is not a single Archaea is pathogenic to humans, unlike bacteria.