For the filter, When editing the view, I've added some custom fields to query.
Setup as follows..
field: somefield
comparison function: >=, Numeric,
URL parameter, somevar
The I've set up the control settings.
Field: somefield,
Label: Some Field
Input Type: Checkboxes with "Use existing custom field values when showing this control"
A few of the values in that field are set to 0 (zero) and they do not show up in the filter control on the front end.
