Here's a totally uninteresting shot but I saw a bright light and figured I'd try to get my SMC Pentax-a 50/1.2 to flare wide open... with moderate success:
It has no problems producing bucketloads of coma (see top left corner) but flare is not really in this lens' repertoire. The other lens I can't get to flare at all is the Leica 90AA but that's to be expected.