I use 30+ different passwords for different purposes. I never write the actual passwords down anywhere but instead I write the hint of the username/password for each site. Here's a fake example:
sitename.com: c4 - t/5r
sitemore.com: mrc - pp:9
If someone manually digs around, they can find what the usernames 'c4' and 'mrc' stand for. However, nobody other than me knows what 't/5r' and 'pp:9' expand to and I will never forget what they mean. Sure, it does theoretically make it slightly easier to brute-force my passwords but if 't/5r' = 'tempest/ariel5randa' then brute-force will take forever anyway.
If the browser doesn't auto-fill the password, I just have to look up a single list and takes me seconds to type the password. Whenever I sign up for a new site, I just add the username/password hint and forget about it. I've been using this system for well over a decade and have never had any login problems anywhere.
Essentially you are using a private hashing algorithm. You're trading a bit of convenience for a good chunk more security. If it works for you keep doing it. The important thing is you are using good passwords and segregating sites.
Are you sure that stands up to a targeted attack? If, randomly guessing, those are WoW accounts you now have to keep your HN, WoW and e-mail accounts separate...
Pretty sure it would stand up to a targeted attack. Here's a few of my actual password hints:
/-/
**
1m;
Feel free to login to any of my accounts. And I do keep most types of accounts separate. Bank password is different from Credit Card is different from email is different from HN.
If the browser doesn't auto-fill the password, I just have to look up a single list and takes me seconds to type the password. Whenever I sign up for a new site, I just add the username/password hint and forget about it. I've been using this system for well over a decade and have never had any login problems anywhere.