Many of these rules have been imported from Jeff Rients' Cinder House Rules, but some exceptions are be noted. Some are original, and some have been tweaked a bit.
Character statistics are rolled 3d6 in order. The human classes do not require any stat minimum to qualify, so you can play a stupid Wizard, foolish Cleric, klutzy Thief, or puny Fighter in the dice rolls go that way. If you are unhappy with your character to the point of considering kamikaze attacks, at least get killed as smartly as possible by absorbing some hits that might land on better qualified adventurers.
Every character receives one Awesome Point per game day. Awesome Points can be spent to replace any die or dice roll with a d30.
I use Jeff's rules for carousing. In brief, characters can spend a lot of gold on debauchery and convert it into experience. This runs the risk of drunken mishaps, however, so drink responsibly. The minimum investment in this sort of revelry is 100 gold sovereigns.
A natural 20 on the 'to-hit' roll indicates a critical strike, and does maximum damage. A natural 1 indicates a fumble, and something bad happens.
The damage your weapons do is mostly determined by your class, not your weapon. Fighters usually do 1d8 damage. Wizards do 1d4. Everybody else does 1d6. Some weapons stink and do one die worse, and some are brutal and do one better. Pick your weapon because of its awesomeness, not its damage. This rule is mostly a harkening back to original D&D rules.
When a wound would reduce a character to zero hit points, the player rolls on the Death & Dismemberment table. The results may be instant death, delayed but certain death, or even a burst of adrenaline. Probably, though, you'll still end up dead.
To avoid the hassles of starting over with 0 XP and rolling up a new character in the middle of a game, the players are encouraged to recruit henchmen. Henchmen earn experience at half rate and normally expect a half share of treasure. They are generally loyal and normally the player runs them as secondary characters, though the DM reserves the right to step in when needed to protect the interests of the NPC proletariat and to make morale checks. If a character with a henchman is incapacitated, the player may immediately promote the henchman to full PC status. The new PC may be bumped back down to the ranks of the sidekicks should the original PC be raised from the dead or unpetrified or whatever.
When an adventurer dies and the party is unable (or unwilling!) to have them raised from the dead, a promoted sidekick (see above) may opt to give the corpse a Heroic Sendoff. This requires at least 24 hours and something cool like a bigass funeral pyre, the raising of a burial mound, or a funeral ship floated down the river. The corpse must be armed and armored for combat, as appropriate to the class of the character. Each party member may donate up to 100gp times the level of the stiff as additional grave goods, the amount being spent is converted to bonus XP for the donor. Each party member may also donate one magic item to the grave. Scrolls, potions, and other one-shot items net a bonus of 250xp, while more permanent items get you 1,000xp. Magic items that would have been unusable by the deceased do not count.
When the adventure is over and the characters get at least a full day and night of rest in a safe place, they reroll all their hit dice for healing. If the roll is lower than their current hit point total, it is unchanged. Until the adventure ends, characters can only regain one hit point from each full night's rest. A full night's rest in town doesn't mean the adventure is over. The character needs a whole day off.
Any time a PC runs out of hit points that character is allowed a saving throw versus Death if they haven't already failed a saving throw to get 0 hp. If the roll is made the character is unconscious and at 1 hit point. Without aid from an ally, the character will die in 1d4 rounds.
This rule comes from Trollsmyth. With this houserule, you get the usual -1 to your AC with a shield. However, any time you take damage, you can opt instead to say your shield absorbed the force of the blow. The shield is shattered and must be discarded, but you don't take any damage from that hit.
If you want to do something totally awesome, you can shift down the threshold for a critical hit by shifting up the threshold for a critical failures. In other words, you can say that you'll crit on a 18-20, but then you'll fumble on a 1-3.
Clerics must have a declared allegiance to one of the setting's faiths.
We use the simple 2d6-based chart from Jeff Rients.
I use Dyson Logos' rules for 2d6 thievery. Basically, all those annoying percentile roles for thief skills are replaced with 2d6 checks.
A wizard or elf can cast any spell that he has copied into his spellbook, without memorizing it. It takes six turns (one hour).
A wizard or elf can re-cast any spell that she memorized for the day, at the cost of one hit point per spell level.
Wizards and elfs begin with a spellbook with (3 + Int bonus) spells written in it. One of these is always Read Magic.