With the introduction of 3G, and especially 4G, mobile Internet access is no longer considered inferior to home broadband. In fact, in certain locations it can actually be much faster than many residential DSL plans. That said, as you roam around, even within the same city, you'll experience changes in speed and coverage because it is still just a cell data connection.

From left: T-Mobile Sonic 4G, Clear Spot 4G, Sprint MiFi and T-Mobile Rocket 3.0 4G Laptop Stick

T-Mobile Sonic 4G Mobile HotSpot

The good: Compact and good-looking, the T-Mobile Sonic offers mobile Internet access for up to five Wi-Fi clients via T-Mobile's 4G and 3G networks. The device has long battery life, works as a tethered modem, features an SD card slot and supports text messaging.

The bad: Data speeds could use some improvement, comparatively. Its included limited-data plans are rather expensive, and the router's connection speed is throttled when the monthly data caps are reached.

The cost: $99.99.

The bottom line: Well-designed and reliable, the Sonic makes a very good travel companion. 3.5 out of 4 stars

Clear Spot 4G (Apollo)

The good: This mobile router provides fast cellular Internet access to up to eight clients at a time, with affordable unlimited data plans. The Apollo incorporates a large LCD that shows helpful information about the device, and the battery lasts a long time.

The bad: The Apollo doesn't support 3G, Wireless-N or text messaging and is comparatively bulky.

The cost: $99.

The bottom line: For those who live or travel within Clear's 4G coverage, the Clear Spot 4G Apollo is an excellent mobile-broadband option. 4 out of 4 stars

Sprint MiFi 4082 3G/4G Mobile Hotspot

The good: Good-looking, compact, easy to use and features Wireless-N. The device comes with an affordable unlimited 4G data plan, includes GPS and network storage functionality, and has decent battery life.

The bad: Sporadically doesn't work well with certain Wi-Fi mobile devices and can support only five wireless clients at the most. The device runs hot at times and its 4G connection is comparatively slow.

The cost: $0.00 to $79.99.

The bottom line: For mobile users who travel within good Sprint 4G coverage areas -- especially those with laptops -- the Sprint MiFi makes a good companion. 3.5 out of 4 stars

T-Mobile Rocket 3.0 4G Laptop Stick

The good: This USB modem provides a fast Internet connection for a single computer and gives unlimited access to T-Mobile Wi-Fi hot spots. The device has a nice design and embedded connection software for both PCs and Macs that also supports text messaging.

The bad: Comes with expensive and limited data plans that throttle down Internet speed when the data allowance is reached. The modem itself is rather bulky and its download speed fluctuates a great deal.

The cost: $79.99.

The bottom line: The T-Mobile Rocket provides a very good mobile Internet connection in areas where T-Mobile 4G or Wi-Fi hot-spot coverage is available. 3.5 out of 4 stars