I've looked at SHA1_Pass when it was posted here on HN a while back, and I'm not impressed. You have to memorize a passphrase, which is only marginally easier than remembering a master password, but you also have to remember an individual word for each account/website. Yes this is easier than remembering individual passwords but not as easy as just remembering one master password that unlocks an encrypted database (like Keepass). From the FAQ for SHA1_Pass, it says "when your bank asks you to change your password, just increment your word from BILLS to BILLS1 or BILLS2". More stuff to remember, which BILLS was I on again?
Additionally, some accounts have restrictions on usable characters or password length. The FAQ for SHA1_Pass says "try base64 half-encoding, its only 14 characters, and if that's too long maybe you shouldn't be using that website". Well I'm sorry but some BANKS do not allow passwords that long. You and I both know it's idiotic, but some banks have a small maximum password length, and some of them even restrict you to alphanumeric characters only.
I applaud SHA1_pass for trying to be innovative, you don't know what works unless you try it, but it looks like the result is a failure to me... too much complexity generated around the goal of trying to make passwords easy to remember, yet hashed to be secure. Just generate a random password with Keepass, whatever length and character sets you want, and store it.
What's the big deal? Yes, there's a chance that Keepass didn't do their encryption properly and your master password will be crackable, and someone will hack into your dropbox account and then have all your passwords. But with SHA1_pass there's also a chance someone will guess or socially engineer your passphrase, and since all your site words are "facebook" for facebook etc etc they too have full access to all your accounts.