(Or kamikaze packet) A packet with every single option set for whatever protocol is in use. The term doubtless derives from a fanciful image of each little option bit being represented by a different-coloured light bulb, all turned on.
RFC 1025, "TCP and IP Bake Off" says:
10 points for correctly being able to process a "Kamikaze" packet (AKA nastygram, Christmas tree packet, lamp test segment, et al.). That is, correctly handle a segment with the maximum combination of features at once (e.g. a SYN URG PUSH FIN segment with options and data).
Compare: Chernobyl packet.