While cleaning up some records today, I noticed a few videos whose titles appeared in the catalog as:

  [videorecording]

I wondered if this was some sort of intense art film with no title, or if someone was intentionally or unintentionally messing with catalogers by giving their film a title more often seen as a GMD. (Was this a film about the history of the GMD??)

I clicked through and found that it was a perfectly normal film, with the title:

  $100 a day : justice and reparation in California's
    legal system

And this had somehow ended up in the MARC record as:

  245 00 ǂ1 00 a day : justice and reparation in California's
    legal system

The dollar sign is a particularly dangerous one to have in your data if you’re not careful with your processing. In many languages it signals the beginning of a variable, so “$100” may have unpredictable (or erroneous) behavior. It’s also a common convention for representing the subfield delimiter in a MARC record, so:

  245 00 $a $100 a day

might have looked like it contained an empty subfield $a and been cleaned up in text to form:

  245 00 $100 a day

and then reinterpreted as:

  245 00 ǂ1 00 a day

It’s important to sanitize your input!