premium/restricted channel connections implemented, configure at yoursite/channel/nickname - this basically redirects "follow" requests to a premium channel's sell page if it has one configured. You can still click through and create a connection request (introduction), but this provides a means for the channel owner to state their terms. If you don't abide by the terms, you will likely be blocked or the channel deleted. This facility is extensible in a number of ways.

include/Contact.php

@@ -15,13 +15,20 @@ function rconnect_url($channel_id,$xchan) {
 	if($r)
 		return '';
 
+	$r = q("select * from xchan where xchan_hash = '%s' limit 1",
+		dbesc($xchan)
+	);
+
+	if(($r) && ($r[0]['xchan_follow']))
+		return $r[0]['xchan_follow'];
+
 	$r = q("select hubloc_url from hubloc where hubloc_hash = '%s' and ( hubloc_flags & %d ) limit 1",
 		dbesc($xchan),
 		intval(HUBLOC_FLAGS_PRIMARY)
 	);
 
 	if($r)
-		return $r[0]['hubloc_url'];
+		return $r[0]['hubloc_url'] . '/follow?f=&url=%s';
 	return '';
 
 }