Many of the Euros use homebuilt "hedgerow howlers" like the Commando, Lulu, Corsair, Dutch Quad, et al. These are set up in an out of the way place with a battery and antenna, and a pre-recorded show on an MP3 player is started. The ops consider the setup expendable, and leave it running. They will keep an eye on the location from afar and if they deem it safe, will retrieve the setup afterwards, to use again the next time.
There IS another way - provided that you don't have a psychological need to always be playing for the crowd. Be frequency agile. The way I do it is to have a whole collection of homebrewed 1 watt exciters that I use to drive a linear amp. I swap out band specific dipoles and band specific low pass filters as needed. I'm on often, but I only show up on 43 meters once or twice a year and rarely operate on that band from home. It isn't as expensive as it may sound, because most of what I use is homebrew. Also, I have built my "armada" up over a number of years. This way of operation will absolutely NOT garner you fistfuls of reception reports, but I find it a lot of fun to bushwhack unsuspecting SWLs here, there and everywhere. The few surprised and (usually) delighted reporters to my email drop seem to agree.
I guess if you're just starting out, you can carefully operate occasionally, just like the crowd does - being careful not to cause RFI with anybody. But once you've been at it a while, you should figure out a more secure system that will work for you. Of course, you could always buy one of those "golden horse shoes" that cmradio was talking about...
