Binder Mark of Making Battle Nanobots. This one comes from SKRP and me, sometimes lurkers can get things on their own
Binder 1 with Improved Binding or Binder 3+ can bind Green Lady* and use one 1st lvl spell as a SLA once every 5 rounds.
Skip to the Dragonmarked handbook and it's Summon Marked Homunculus (pg 154).
As a SLA it should not require the Mark of Making, but even if we take it as needed to get homunculi tier, we still get to make a free Homunculi that exists 1hour/level and when reduced to 0hp deals d6 damage to everything adjacent, but you. Mind you, you can use this to make a huge amount of intelligent dimunitive Expeditious Messengers, who can fly with 100ft speed, find their victims and blow them up in a chain reaction (2hp) of [untyped] damage.
For extra points you can use them to deliver villainous monologue before killing the target.
*She's not official per se, but she's a part of an official campaign, so it's at least notable. YMMV.