As someone else mentioned, Litecoin. Not in passwords but in "mining" (proof of work). It resisted GPU for a while until it didn't. Although the difference betw

As someone else mentioned, Litecoin. Not in passwords but in "mining" (proof of work). It resisted GPU for a while until it didn't. Although the difference between CPU and GPU was not big (much smaller than with SHA256). The work factor was too small and it couldn't be changed easily. After 4 years, though, nobody "cracked" it. The work factor of a password database can be changed easily, either by re-hashing every time someone with the old scheme logs in, or by hashing all the hashes more.