A port replicator is nothing new. It's an easy way of adding more connectors to your computer via USB 2.0. The more advanced models often have an audio and monitor port, in addition to the USB ones. This new HP 3005PR USB 3.0 Port Replicator goes even further, with a USB 3.0 connection and lots of ports.
The little box has a pretty basic design. It's a black cuboid bar measuring 22 cm x 2.5 cm. Both the front and the back have connectors, which is practical if you have it sitting on the table. You can run the bulk of your cables from the back, and then you have two easily accessible USB 2.0 ports left on the front.
If you want to attach a fast memory stick or external drive, you need the back side. Personally we probably would have designed it the other way around. Aside from the two USB 3.0 ports, the back also has two USB 2.0 ports, putting the total at four.
The HP 3005PR (H1L08ET) also has audio in and out. While most laptops have their own audio connector, it's certainly useful. If you have the replicator sitting on your desk you can keep headphones or speakers connected to it, without having to unplug them from your laptop each time you sit down.
Another practical addition is the ethernet port. Especially if you're the proud owner of an Ultrabook that often don't have one anymore, this is great to have if your wireless network isn't the fastest. The HP 3005PR has a gigabit netwerk port. Many USB 2.0 models have Fast Ethernet, which is 10 times slower.