This is a trick I hinted at in my guide to sorcerers, but did not make explicitly clear until today. I'm going to make it a separate thread so it gets some attention.
So let's say you cast Arcane Spellsurge, and bombarded your enemies with a mighty Maximized Fireball! Well, your full round action spell is now a standard action, which is great! But you have a swift action left, and nothing to do with it! If you don't need to save it for later, you can cast another Fireball on your enemies. Too bad you can't cast another Maximized Fireball, since you're out of standard actions and have no way to reduce the casting time of your metamagicked spells...
Unless you took the Metamagic Specialist ACF from the PHB2, you can apply metamagic to your spells without incurring additional casting time 3+Int mod times per day, which you can use to "toggle" your casting time with Arcane Spellsurge.
Arcane Preparation also works for this, since preparing a spell with it does not increase casting time.
Sadly, Rapid Metamagic does not mesh well with Arcane Spellsurge.