Can you name them Dr?. Thanks
Not all of them, but there's a lot of Dell Laptops (over 17") that have a spare bay for an additional drive.
Sager X7300 can take 3
There are a few out there but you'll find that (purely due to space) they tend to be the larger laptops.
Some have the space but don't have the socket soldered to the board (as some manufacturers use the same board for different machines) don't try to solder one on as even if you did the BIOS isn't set up for it.
Sometimes you'll find the socket there but you still need to get an adapter and/or caddy to hold the actual drive. It's still fairly easy once you get the bits.