I've created a macro which allows you to link to Snip attachments from the attachment text.
You use it like:
{attachment:<attachment name>}
I'm not sure where I should submit details of this thing to get it onto the list of contributions. In the meantime, you can download it from
here.
The download is a gzipped tarball containing source code and a prebuilt jar file. Install it as you would any other Macro (i.e. copy it into the applications lib directory). In case it isn't obvious, when you unpack the tar file, the Macro is in the following location:
Attachment/dist/AttachmentMacro.jar
The source is included so you can modify it and make it better if you like. :-)