Divine Secrets of the Space Marine Brotherhood?

If there's one thing I believe space marine armies need, it's force multipliers. The two assault cannons you could (previously) take in a 5-man terminator squad was a perfect example of a force multiplier -- having those two assault cannons greatly expanded the damage that unit could do per turn. Now that we've all had a chance to get a look at the new marine codex (and hopefully digest at least some of it), what combinations of units/abilities create meta-units whose total is greater than the sum of its individual parts?

Here in Austin, there are a few favorites that seem to be rising to the top:

1. Captain Lysander joining a full squad of Sternguard: with his "Bolter Drill" special rule, those Sternguard will be pumping out the Hellfire rounds with re-rolls to hit and re-rolls to wound. Plus, re-rolls to hit means you'll never overheat when firing the Vengeance rounds. Nasty!
2. Join an epistolary librarian with the Gate of Infinity power (probably coupled with The Avenger) with a full squad of Sternguard. Add in either several drop podding units or scout biker units with locator beacons and it's bounce-tastic, no-scatter, deep-strike-to-where-you-really-wanna-be fun. Every time your movement phase comes up, if your Sternguard aren't where you need them to be (for example, if you need to avoid an oncoming charge or put yourself in rapid fire range), have the librarian cast Gate of Infinity and bounce out. Also, if your Sternguard/librarian get stuck in an assault you really don't want to be in (which is all of them, because every round they're assaulting is a round they're not shooting), Gate of Infinity out to safety (and by "safety," I mean "rapid fire range to the unit you were in assault with"). You don't have to have a few locator beacons around to use this combo, but I think it's very highly recommended to avoid that whole deep strike scatter issue, which can really ruin your whole day (or at least your battle plan). Also, if you're like me, you want to do everything you can to remove the potential impact random chance can have on your army/units. I originally thought this power was used during the librarian's shooting phase, but an anonymous commenter (who may go by the name "lord-o-doom") pointed out that GoI is cast during the movement phase. So while it may be a little less useful than I originally thought, this combo is still my current favorite.
3. Drop-podding a pair of tooled-up dreadnoughts (either ironclad or venerable) into your opponent's backfield and then opening up with heavy flamers and/or multimeltas/assault cannons/twin-linked auto-cannons. To follow that, charge on in for some DCCW/Seismic Hammer close combat lovin'. Support these dreads with a full squad of Sternguard (probably with a librarian rockin' Gate of Infinity) and maybe a full tac squad (or two) and you're in business. Just make sure you have enough drop-podding units to get all the units you REALLY want in the backfield on the first turn (which probably means you're going to need at least 5 units with pods). Don't forget locator beacons on the pods!
4. I created a 2000 point list with Pedro Cantor and 90 other marines (3 full Sternguard squads and 6 full tac squads). That makes a total of 91 power-armored marines on the table, and with Pedro...90 of them are scoring. Granted, they're all footsloggin', but I think it would be pretty impressive (and not to mention, hard to kill).
5. Honor Guard. Yes, they're ridiculously expensive. But let's think about it: for 385 points, you get 10 Sv2+ marines with power weapons, including the company champion and company banner. That will yield 51 S4 power weapon attacks on the charge (4 from the champ, 27 from the others, 10 from the company banner and 10 for the charge bonus) and 41 S4 power weapon attacks during a regular round of assault. If the S4 doesn't float your boat, you can give 'em all (or just a few) relic blades for some S6 power weapon goodness (at the cost of one attack for each model that has one). Giving the entire squad relic blades costs 150 points...and for the same price you can give the whole squad auxiliary grenade launchers for some added shooting power if you like. Granted, you have to take a chapter master to get them, so choosing one with some heavy CC power is probably a given (or not, they can run around by themselves). At first I didn't think these guys were worth it, but the more I look at what they're capable of, I think they're at least worth testing out...

What do you think of these combos? What interesting little gems of space marine goodness have you found lurking in the new codex? Share with the group and discuss!