Chuck Houpt has developed a small utility for converting Mac picture files to SVG: pict2svg aims to leverage existing tools that can already output in the PICT format.

At the moment, only a subset of the PICT format is supported: text, lines, rectangles, ovals and polygons. The author plans to add in support for fonts, rounded rectangles and bitmaps.

Houpt writes:

My goal is to create [a] utility to compliment low-end graphics programs such as ClarisWorks/AppleWorks that generally use PICT format. This will be useful for converting simple diagrams, spreadsheet charts, etc to SVG.