Potion and/or Wand of Cloud wings is a nice, cheap way to go for +30' to fly speed only. Plus it is not an enhancement bonus, so it stacks with Haste (or Boots of Speed).

What book is that one in, Ith?

edit: Nevermind, spell compendium. Thanks. That's actually very useful. 1 hour/level duration, druid spell. . . I don't even need the potion/wand, I can just cast it myself.

Does the ability to use the spell Fly a staff allow to take the feat Fly-By Attack?

Collar of Umbral Metamorphosis. +10 feet all move speeds, unnamed bonus.

If it doesn't have to be items there are a lot more options such as permanent spells.

Dang. The continuous version of that would actually be perfect, except it's a collar, so it takes up the neck slot. Since I'm a cleric, that's pretty much dedicated to my periapt of wisdom. Curses! Just going to have to stick to using spells I guess. Aerial Alacrity and Cloud Wings for me.

MIC rules for standard properties such as enhancement bonuses to wisdom. Not a problem.

There's also some first level sorcerer spell that gives +30 for 1 hour a level or so. UMD it.

Complete Champion has an alternate class feature for Sorcerer that lets them cast spells from any domain once per day. Could you combine this with the Spell domain so you could cast Anyspell & Greater Anyspell thus drastically increasing your Sorcerer's flexibility?

Could a warlock use a meta-magic rod effect their Invocations and Eldritch Blast?

Can metamagic effect those? If so, I'd say yes.

Complete Arcane says that the Sudden Meta-magic feats can spell-like-abilities, but it says nothing about the Meta-Magic Rods.