These hybrid devices usually record onto Secure Digital (SD) cards, and yes, you can carry a few high-capacity cards on the road with you and swap them as necessary. The amount of video that will fit on a card depends upon the device's resolution and compression options. For example, Sanyo

claims that you can fit a little more than 40 minutes of HD video on a 2GB card, while Sony rates the Cyber Shot DSC-M2's 30fps VGA movies at about 40 minutes per 1GB. And remember--those capacities apply only if you don't shoot any stills. However, as long as you don't plan to shoot epic features while you're traveling and can accept the limitations of these devices--the video will not look as good as most MiniDV recordings, and the MPEG-4 encoding they use makes editing the movies difficult--they sound like the right solution for you.