I have a set for Froslass. This set already existed, but I've modified it slightly.
Froslass w/ Leftovers/Brightpowder if on a Hail team
Snow Cloak
Bold
248 HP, 228 Def/SD, 32 Def/SD
Ice Beam/Shadow Ball/Hidden Power (Fire)/Blizzard (If on a Hail team)
Spikes
Taunt
Pain Split
I call it "Spin Blocking Froslass" or "Stallbreaker Froslass". This is because this Froslass is designed to, rather than being a lead, to be a mid-to-late game Pokemon. This set exercises what is arguably Froslass' most useful trait: It's a spin-blocker with a hazard move. The bulk allows you to block Rapid Spin and survive most Rapid Spinners' other attacks (I don't have logs, just experience from battling and some general calcs I forgot). Taunt is really the crux of this set, and why I labeled it an anti-stall Pokemon. You come in to block Rapid Spin from Forretress, for example, and Taunt it on the next turn. Forretress is now useless against you, as Payback and Gyro Ball are both survivable. You then begin Spiking. This works against Stall Pokemon in general, as Froslass' blistering base-110 Speed allows you to out-speed most defensive Pokemon, Taunt while the EVs let you shrug off their weak attacks, and begin Spiking. Obviously, it's good to have a phazer with Roar/Whirlwind to take advantage of the hazards, and a sweeper to take advantage of the damage. A Rapid Spinner of your own is nice, as it lets Froslass come in more often. Pain Split is there to provide some "healing", and it helps that most defensive Pokemon have more HP than Froslass, i.e Blissey. Also, having a Pokemon to spread Toxic around your opponent's team is great too. A Tentacruel with Toxic Spikes, or Stallbreaker Gliscor works well. This allows Froslass to actually outlast an opponent's Pokemon. The attacking move is up to you. I use Ice Beam since I'm not attacking so much and it's my best move, but HP Fire does a number on Forretress, and Shadow Ball has STAB and hurts Starmie.
I use this set in tandem with Gliscor and Tangrowth to support a DDtar sweep. It's a nasty combination, with Gliscor's Toxic poisoning a good deal of the opponent, and Mojombo's Leech Seed sucks health away and gives it back to me. I have SR support as well, so switching in sucks for my opponents. I have many games where opponents switch in and take 18% from Spikes, 12% from SR, 6% from Sandstorm and 12% from Leech Seed. That's 48% on one turn, which is amazing.
Obviously this set isn't as effective against pure offensive teams, since it can't weather repeated assaults from incredibly powerful attackers. Base 70 defenses aren't amazing, after all. But it really does a number on Stall teams, and if you have a second Ghost for some reason (Or if you use Britscor for a Spin-blocker like me... dick) it really screws stuff up.
Some of you might say the set sucks since it isn't as bulky as some other Pokemon, and others might hate me since I didn't really come up with it. Here's another Spin Blocking Froslass I DID make, and this one trades beating on Stall teams for offensive power.
Froslass w/ Life Orb/Leftovers/Brightpowder w/ Abomasnow on the team and massive injection of douche
Snow Cloak
Modest/Timid
252 SA, 252 Spd, 6 HP
Shadow Ball
Hidden Power (Fire)
Spikes
Sleep Talk/Taunt/Ice Beam/Blizzard (If on a Hail team)/Pain Split/Substitute/Toxic/Thunder Wave/You get the idea
This Froslass comes in on a Rapid Spin, and does one of thwo things:
1. Spikes
2. Kills the Rapid Spinner
It's pretty simple. STAB Shadow Ball OHKOs Starmie, and HP Fire usually OHKOs Forretress. Since very few teams pack more than one Rapid Spinner, this set tends to make your hazards permanent. Leftovers gives you recovery, Life Orb grants you more power, and BP is just to be a jerk. The final move is up to you and what you feel like using. T-Wave/Toxic cripples switch-ins, Taunt lets you bash on Stall to an extent, Ice Beam/Blizzard is for extra STAB, Pain Split "heals", etc. I'm not 100% sure if Froslass learns Sleep Talk, but if it does, I'd recommend that for some extra utility. It works pretty well, but beware LO Starmie running Rapid Spin, since they'll KO you pretty handily. I shouldn't have to say it, but USE FROSLASS FOR MID-TO-LATE GAME. It works great OUTSIDE the lead position, and this set was not designed to do well in the lead spot to begin with.
EDIT: I've done the calcs, and you need Life Orb to OHKO Rapid Spinning Starmie, and even then it needs to switch into SR to always be OHKOd (Factoring in Lefties). You can run Modest, though, and always OHKO. Timid HP Fire ALWAYS OHKOs Defensive Forretress regardless of your item, but Specially defensive variants need some wearing down to get the OHKO with Life Orb. Modest Froslass with Life Orb will ALWAYS OHKO Forretress with HP Fire after Forretress switches into SR (Not factoring in Lefties, since some Forry run Shed Shell). Still, after taking a hit, both of these Pokemon are severely crippled. I have, however, changed the set for Modest nature, since Timid Froslass still doesn't outspeed RS Starmie.
Well, I hope this helps Froslass get the love it deserves. :)
EDIT: F*** YEAH AGILENITE! I've been using that set since the day Mence was banned to great effect (Well, not that exact set, but 252 Atk, enough speed to outspeed Scarfed-100s, and then all HP). It's great with a lot of support to weaken counters, and then just lower the boom. Outspeed most of the popular counters, and from there your sweep is pretty free.
