When most people hear the phrase wireless portable printer they instantly assume that it's only useful to those travelling on the road that need work constantly printing out. This couldn't be further from the truth because in fact they could be more useful in your home than anywhere else.
Your average family has a father, mother and two teenage children - all of which either have a computer/laptop if not access to one at the least. All of them also will need work printing of, either job-related for the parents or homework related for the children. You may be asking where the problem is, but if you've ever lived in a household such as this you'll realize that even though they may all have their own computers they certainly don't have their own printers. There's usually only one household printer divided amongst four people, and it's usually situated in the dad's office area.
This means that the father, the most likely provider for the family who'll almost certainly be one of the most stressed will be getting bombarded by his wife and children for requests about getting printing done. USB sticks will be waved in front of his face and emails will be sent, and at some point it simply became his responsibility to handle all the printing work.
But why should he?
A wireless portable printer allows you to do two things, firstly it allows you to print wirelessly from your computers without the need for cables or usb sticks. Secondly it can be moved from room to room, this means that if someone wants someone printing it's their responsibility - not their fathers.
If they need something doing then they can go to the room where the portable printer was last used and handle it themselves - without stressing an already stressed out dad!