[Genome] Bed file Format

[Williams, Alan]

We're interested in using the BED file format but would need to add some
additional information on a per entry (bed line) and per file basis. It
isn't clear from the format description whether this is possible or not.
 
For example, we'd like to:
 
- add comments (ie equivalent of "#" in gff)
- add meta info (ie equivalent of "##" in gff)
- add extra information regarding a given bed line, perhaps as
additional columns of information (ie a list of probe IDs from which the
bed entry was derived)
 
Is it possible to do this and still have a "valid" bed file, or should
we consider using GFF?
 
Thanks,
Alan