There are a huge variety of hubs for various connections. An 8-port hub is typically an ethernet or USB hub, and there are a wide selection of manufacturers for such products.
Yes, you can daisychain multiple smaller hubs, or buy a router.
Yes
Yes
I know of no such adapter. 5 lug hubs are smaller and more lighter duty than 8 lug hubs. Even there were such an adapter, I wouldn't recommend putting an 8 lug wheel on a 5 lug hub. Bad Idea.
The Shimano FH-RM30 8-speed freehub body is compatible with various types of cassettes and hub configurations. It can work with 8-speed cassettes and is designed to fit hubs with a 135mm spacing. Make sure to match the cassette type and hub spacing for proper compatibility.
section 8 housing
There are a few top-rated companies that manufacture 8 port switches. Some top rated 8 port switch manufacturers include NetGear, Cisco, Linksys, and Monoprice.
One has 3 one has 8
parallel port if you want to know why go to it140 if you know what that is.
I worked in a Chevy dealer for 17 years, and have replace many front hubs on the Chevy trucks. The newer styles seemed to have poor quality hub bearings, even in the 8 lug HD configuration. In fact, I replaced many of the 8 lug hubs for bad bearings, and almost NO 6 lug light duty hubs. The 90's style hubs virtually never went bad if they weren't subjected to abuse.
Mike Franks & the Port to Port Killer
section 8 still exist but during our hard time its not easy getting into