Cover Art by Miguel Santos
Note: I did a more in-depth review of game mechanics analysis over in this thread at Min-Max Boards if you're interested in that kind of stuff.
There are many third party classes out there for Pathfinder, and it's easy to get lost in a sea of supplements. And a lot of existing options are derivative, recycling old mechanics instead of seeking out new rules for the game. While there's nothing wrong with updating old information, it can get difficult at times to find a fresh take on iconic concepts, much less ones which do it well.
The War Dancer succeeds on both fronts. It is a martial class which is geared around a "controller" role, that of using the environment, mobility, and trickery to exploit and alter enemy positions on the battlefield. In short, it uses a limited-use daily resource of dancing as its iconic ability, and there are 13 possible dances to learn. They ranged in use from elemental dances which can knock down enemies with earth tremors, ranged energy attacks, feats of impressive mobility which allow the dancer increased speed at its most basic and even dimension door teleportation at its most powerful! There's even dances which contain nigh-essential features for fighter types, such as extended reach and single attack rolls which harm multiple opponents. A tiny few dances are lackluster in power and use, but overall most have an effective application in many situations.
Beyond this the War Dancer can also cast spontaneous divine spells up to 4th level, and while most are more geared towards buffing and combat applications instead of utility, the class draws from a variety of existing spells from the cleric to the ranger to the wizard. There is also two new archetypes, the Arcane War Dancer and Southern War Dancer, which grant the class limited access to the abilities of the magus and bard respectively while allowing armor proficiency.
My main complaint about the class is that unless one goes for an archetype, the lack of armor use makes the War Dancer very easy to hit for a melee fighter, and will require a lot of healing resources unless they make for good optimization and reach weapon extension builds. Aside from this, the War Dancer has a variety of abilities to make for interesting stunts in combat beyond the typical "charge, full attack, manyshot/rapid shot" which tends to dominate Pathfinder martials and is a worthy purchase for its price at $2.99.
The War Dancer can be bought at Drive-Thru RPG/RPGNow, Paizo, and the D20 Pathfinder SRD.