not in the UI -- you can create them quite easily using the API though -- I've posted perl scripts that do it in the past.
Got a link?
at it's simplest there is the following perl snippet:
[Sector and Building are two custom properties... I have this code inside a perl function that takes a building and sector as arguments and creates a group with the members in it]
$swis->Invoke("Orion.Container", "CreateContainer", [
"Group for $sector nodes in $building",
SOAP::Data->type('xml' => "<ArrayOfMemberDefinitionInfo xmlns='http://schemas.solarwinds.com/2008/Orion'><MemberDefinitionInfo><Name>$building Devices</Name><Definition>filter:/Orion.Nodes[CustomProperties.Building='$building' AND CustomProperties.Sector='$sector']</Definition></MemberDefinitionInfo></ArrayOfMemberDefinitionInfo>")]