My paranoia forces me to download *everything* I own as soon as I can.
For now, I'm keeping my GOG library on the internal HDD; I used to back them up in an external one, yet I had to convert it in a storage for work documents, images, etc.
I guess I should buy another one asap and transfer all my goodies!

P.S. I download all the bonus goodies, but usually only the English installer.

I used to. Then the installers started updating and i moved to windows 7 and realized I had backups of old installers that may or may not work with my current machine. Then I realized GOG will usually keep its installers updated, that I really had no need to keep files of games I won't even play in who knows when and it took a lot of time to back everything up, on the off chance that GOG went belly-up someday.

Now, I'm kind of risking it. Sometimes I'll download games and back them up if I'm really interested in them and other games i don't really bother, since I got them for cheap on a sale and just bought them because of price, not of want or need.

Backups aren't forever really. As soon as you have a new OS, old games get clunkier and clunkier, just like your old, original game CDs and DVDs that pushed you to re-buy a working copy from GOG in the first place.

For the most part i have only the games i am currently playing backed up.
The exception being larger games such as TW2 etc...

May rethink this if i can find a deal on a external hdd.

Most of my library (135 games total) are backed on DVD's with all bonus content and each setup file accompanied by an "MD5.txt" file containing MD5 strings.

18 of the games are still on my drive though, some because are fairly new like Divinity OS and Wasteland 2, big games updated frequently and not worth wasting discs others because they're too small and not worth wasting a disc for a 2gb usage.

i dont like that either
a disc is either getting used for the full 4.4 gig or not at all

im less stringy with cd's

I tried to backup my games but having a 100+ and they are always updating is really hard to keep track of stuff so I gave up XD

I back up every game I buy within 20 days or so.

The only store I paid for games I did not back up was Groupees. You can guess why now, can't you.

I have downloaded all games and copied to my external hard disk :D

3TB.

isnt that a bit small ?

I have. To an external drive, because ain't nobody got time to burn all these installers to DVDs. Or at least, I definitely don't.

Some GOG games have been pulled from people's shelves for legal reasons. Also, I like to have offline access to as much as possible. Not having internet for a few years really teaches a certain set of habits.
Nah. I have several hundred games - 400ish? - and 2TB has plenty of room for them + extras. It's all about the average game size I suppose.

i have an obscene amount of hd space ( 9 tb )
everything is kinda small to me i suppose

Not a single GOG game has been permanently pulled from a shelf. What has been pulled for legal reasons are bonus materials and a Mac version of Imperial Glory that GOG wasn't allowed to sell.

Every time I buy a game I DL it and put it on a backup drive. I even have old installers.
I find it interesting that people still put stuff on DVDs, those things are not reliable. Many many many disks over the years suddenly have 0kb content on them. Scary, really. I recmomend secondary HDs that you use for storage only.