Generals Regalia: A reverse of jade monolith. Very useful in decks featuring large creatures. Combo's nicely with Cho-Arrim, Squee, Mother of runes. Works well with things like Earthquake and Hurricane too.
Power Matrix: Yow! Any moderately sized creature becomes a nasty powerhouse. Offensive and defensive uses make this well worth the cost.
Rishadan Pawnshop: I think this may be underappreciated. Combo's with overtaker rather nicely. Or use it on your Phyrexian Negator to keep it from taking damage. Best for removing something you have in play that you don't need now, but maybe later.
Magistrates Scepter: I'd play this in a mana intensive deck, then just let it sit and build counters until it gauranteed a win.
Wave of Reckoning: The new wrath of god, not quite as good, but close, and with different applications. I have found this to be a very useful card almost every time I drew it. Excellent addition to a rebel deck. Spidersilk Armor/Natural Affinity/Wave of Reckoning. OUCH!
Rappelling Scouts: A great blocker, but a bit mana intensive. Sort of a new version of Knight of Dawn with similar applications.