By all means, get your license. In US, the FCC does monitor the frequencies for abuse and fines for operating without the license are currently running in the neighborhood of $10,000 per violation. Each day of illegal operation is typically considered one violation. If FCC doesn't snag you, other Hams will detect you and turn you in; it's called self-policing and is necessary to keep the bands assigned to Amateur Radio available for Hams. Pirates are not tolerated. Hams are particularly good at Radio Direction Finding and they will find you.
The license is not that hard to get; you can get a copy of the self-study book at your local Radio Shack store or online from arrl.org and in about two to six weeks of study you can pass the test. The tests are handled by local Hams and they are typically very helpful. They want you to pass the test.
There are small CW only single band HF rigs that you can stick in a backpack and run off a small battery for when you're way out in the boonies and need to stay in touch. They cost around $150 and with a piece of copper wire for an antenna you can have world-wide communications from anywhere.
As mentioned by other posters, for VHF/UHF, the Yaesu VX series are superb. You can even adapt a homemade directional antenna to one of these and do LEO satellite digital and voice communications using about five watts of power, as well as using them for local tactical communications or wider area comms through a repeater. You can set up a simple interface on your computer at home and have world wide communications via VOIP from your handheld as long as there is Internet available at your base station. If you are in a civilized area there will already be such gateways available locally and you don't have to build your own interface.
Study the book, take the test, get the license. What you learn in the course of study will get you going with a lot of stuff you've only heard about in SciFi.
Drawbacks? Main one is you are only allowed to communicate with other licensed Hams. In an emergency, of course, anything goes, but you may have to defend yourself afterward to whatever authority is in charge in your country.