Someday, they’ll build wireless Internet into every building, just the way they build in running water, heat and electricity today. Someday, we won’t have to drive around town looking for a coffee shop when we need to check our e-mail.

If you want ubiquitous Internet today, though, you have several choices. They’re all compromised and all expensive.

You could get online using only a smartphone, but you’ll pay at least $80 a month and you’ll have to view the Internet through a shrunken keyhole of a screen. You could equip your laptop with one of those cellular air cards or U.S.B. sticks, which cost $60 a month, but you’d be limited to 5 gigabytes of data transfer a month (and how are you supposed to gauge that?). You could use tethering, in which your laptop uses your cellphone as a glorified Internet antenna — but that adds $20 or $30 to your phone bill, has a fixed data limit and eats through your phone’s battery charge in an hour.

Last year, you could hear minds blowing coast to coast when Novatel introduced a new option: the MiFi. It creates a personal Wi-Fi bubble, a portable, powerful, password-protected wireless hot spot that, because it’s the size of a porky credit card, can go with you everywhere. The MiFi gets its Internet signal from a 3G cellphone network and converts it into a Wi-Fi signal that up to five people can share.