The importance of backups
I got it into my head to install XP on a SSD that I'd gotten for my dad so I could play with it before giving it to him. Doing so corrupted my existing Windows install and bootloader.
Fortunately I'd just done a full hard drive backup in my attempts to clone the hard drive and had been making regular online backups. No data loss!
As an added bonus, I have appropriated the SSD. It's about 10GB less storage but SO MUCH FASTER. It's like my four year old Thinkpad is new!
Remember to back up!