Password storage can be a sensitive business, but no matter whether you're using PHPCredlocker or KeePassX, dedicated hardware is best. The more isolated your password storage solution, the less likely it is that unauthorised access can be obtained.
Of course, dedicated hardware can quickly become expensive. Whilst it might be ideal in terms of security, who can afford to Colo a server just to store their passwords? A VPS is a trade-off - anyone with access to the hypervisor could potentially grab your encryption keys from memory (or the back-end storage).
To try and reduce the cost, whilst maintaining the security ideal of having dedicated hardware, I set out to get PHPCredlocker running on a Raspberry Pi.
This documentation details how to build the system, a Raspberry Pi Model B+ was used, but the B should be fine too