All data in time
Check out the Samsung Story external hard drives.
In researching this, it appeared none of these drives, from any manufacturer, was entirely foolproof, with perfect results. But some reportedly better than others, with the Samsung Story at least as good as, if not better than most.
I opted for the 2TB version, and have been happy with it. For what it is worth, it is attractive to look at. More importantly, has been reliable and fast. Reliable would be my primary consideration if using for backup. In my case it is, so only seeing periodic and relatively brief use, but without incident. A drive with Firewire or eSata connections will offer faster transfer rates, with this drive having but USB 2.0, but still fairly fast.
If checking a vendor such as Amazon you'll find that this drive at 1.5TB can be had for less than $100, and 2TB for only a bit more than price specified.
I gave this 2TB drive two partitions, one for Time Machine backup, the second partition the majority of allotted space for general storage. In having since exceeded the storage capacity of this MacBook, I needed most files (particularly movies) elsewhere. This raises a couple points to consider.
If you allow it to, Time Machine will by design override all space on a hard drive, no matter how large it is. It will fill to the brim, until all space is gone, and then delete the oldest files as newer are added. That is fine if your only purpose for an external drive is to backup that on your computer. But it raises the question of why even a 1TB external drive if devoted exclusively to, say, 160GB of a computer in question. It does not, unless for some reason you wish access to many iterations of files you long since forgot about.
For some reason Apple's Time Capsule comes in 1TB and 2TB versions, but without the ability to partition. So if running Time Machine on it, as intended, all they are good for. A perfectly fine solution for some, particularly if having a lot of data to backup, but I wanted most of that capacity used elsewhere.
The advantage of the Samsung Story and other external hard drives is that they can be partitioned, so most of that storage can be used for other purposes. If, for instance, one's computer had 100GB capacity of data, then a partition a bit over at 110GB would suffice. Everything on one's computer would be backed up, only not many older versions of it back to the beginning of time. The caveat in this is how dealing with data beyond that backed up with Time Machine.
I have movies that can be streamed from Time Capsule, since it with wi-fi capability, or using ethernet if wired. But since no longer residing on this MacBook, they were no longer backed up. That is where the Samsung Story came in, as a second external drive able to back up everything on the Time Capsule. Also, since able to be partitioned, Time Machine backup assigned to it. This might seem confusing, but a very valid consideration if using an external for anything but Time Machine backup. The bottom line is ALL data needs to exist in two separate locations, some how, some way. Perhaps this is a moot point, but not if envisioning using an external in part to remove files off of one's computer; reality then: TWO externals needed.
In any event, thus far I am perfectly pleased with the Samsung Story.