An external drive need not be difficult to remove. For example,these units allow you to simply pull the drive out:
http://www.amazon.com/gp/product/B007XJIYRCLikewise, you shouldn't set something up that requires you to manually back up your data. There are a zillion automated backup programs out there.
I've used this one for a long time. There are lots of other options out there tho:
http://www.novastor.com/en/software/windows-backupThat said it is not optimal to rely on a scheme that requires you to grab the drive in case of an emergency. It is possible you won't have time, or you might forget, or you might not even be home (think fire).
Using a local drive can work for this (rotating a drive somewhere off-site like a relative or friends house, or safety deposit box), but you have to be able to remember and make time to do it.
The cloud based solutions are a good way to get both an automated solution combined with a off-site solution. The thing I would be careful about is security. You want to get a solution that is encrypted because, remember, those files are hanging out on the Internet. Make sure you use a really strong password.
Depending on how much stuff you have will really drive the cost. You might consider backup up your most critical files automatically to the cloud, and all your files to a removable disk.
Also remember that a possible situation is that someone could steal your computer and/or your backup hard drive. Optimally you would want to encrypt your sensitive files, both on the normal hard drive, *and* on the backup media.
Truecrypt is a good free encryption solution, but has some limitations interacting with Windows (backing up in-use files in particular).
http://www.truecrypt.org/There are some (commercial) Windows only solutions that don't have this issue because they are willing to pay license fees and sign NDAs that the Truecrypt people are not.
Windows also has encryption capabilities with their higher levels of Windows 7. If you have a lower version, I think they will allow you to electronically upgrade to the other versions at a cost.
Depending on what you have available to you and your capabilities, you could also roll your own. For example, if you have a web site, you could potentially back up to your web server.
Some folks have combined the use of Truecrypt with Dropbox for example.
Some useful DIY components:
Webdrive (mount a remote web based entity as a "drive"):
http://www.webdrive.com/products/webdrive/index.htmlDropbox (mount a cloud drive on your computer with some free space):
https://www.dropbox.com/Truecrypt (serious encryption, free, open source, multi platform)
http://www.truecrypt.org/Cygwin (provide linux utilities on windows)
http://www.cygwin.com/ This can be useful because it includes the "rsync" utility which can be employed as a backup tool.
https://en.wikipedia.org/wiki/RsyncGood luck,
-john