A decent portable solution would be one of those two-drive raid enclosures. Basically, you install two identical drives of your choosing and it appears to your laptop/desktop as one drive, and the data is on both drives simultaniously. If one fails, your data is still on the other drive. If the enclosure fails, you simply move one or both drives to another enclosure and you're back in business. Some of them can take four drives and use raid5 instead of raid1 (mirroring), but are larger of course.
Also, mirrored drives generally are faster than a single drive for reading data because both drives can be accessed for the reads, giving the software/OS two paths for the same data. Writes are slower because both drives have to be written to.
Since I don't use a laptop in my studio much at all, and my home studio is not portable, I use an actual server, with 14 sata drives configured as raid 5 using a hardware raid controller which reduces processing overhead on the server itself.
If I were to copy a 1gb video file from my studio PC to an external drive then compare it to copying the same file to this server, the throughput is not quite twice as fast - 45% faster. This is because servers use all sorts of fancy caching algorithms and also large raid arrays (many drives) get written to in parallel so that reduces the time. Of course one should use gig E ethernet to get the maximum benefit if you go this route.
Anyway, tangent aside, I would consider an external raid1 drive enclosure with two drives - losing your data sucks. I've been down this road many times myself and it really does suck.
Whomever suggested "Ghosting" your laptop was spot on as well. If you don't want to buy Norton Ghost there is a linux-based freeware package that essentially does the same thing, and it's called "clonezilla". I use clonezilla professionally with great success.