Blowfish is an encryption algorithm, not a hashing algorithm. It's not an alternative to MD5.

From here on, take what I say with a grain of salt. I'm not sure of everything.

SHA-1 is stronger than MD5, and SHA-256/512 strong still, but all are known or suspected to be broken for the same class of attacks. None are completely broken mind you. They are broken in the cryptographic sense, which means something like "being weaker than they were originally". However, attacks only get better with time.

Furthermore, the only property that is broken is the ability to produce two texts that hash to the same value, not the ability to produce a text that hashes to a given value. That property is important for document signing, but not for password protection.

Update: Re-organised to clarify uncertainty.

In reply to Re^2: Reverse MD5 by ikegami
in thread Reverse MD5 by raj_monk

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