I had these rattling around my head, so I thought I'd post them.

Tox Nails
Essence 0.3 / Cap 3, Avail 13F, 10,000 nuyen.gif
Tox Nails are like hand razors (and have the same combat stats) but have a narrow groove running along the underside connected to an implanted toxin sack. If set to 'active' mod the sack contracts when the claws cut flesh and inject a dose of whatever toxin has been loaded. In 'passive' mode they act like ordinary hand razors.
The toxin reservoir holds five doses, and is refilled via hypodermic needle. If the injection port is clearly marked this is no problem, but if it is camouflaged then the character must roll intuition+medicine to refill. On a glitch they accidentally inject into the flesh (if the tox nails are in a cyberarm there is no effect other than the loss of the chemical. If it is a meat arm then the character had best prepare for a dose of their own medicine)
Wireless: The character may decide whether to inject after damage is rolled, meaning the dose is not lost if the attack fails to penetrate armour.

Injection Bullet
Like injection darts for people who don't care if you bleed or hollow points that add insult to injury, injection bullets are full-velocity bullets with a polymer cylinder of chemicals inside. Their poor density and fragile construction do them no favors as bullets but they will still blow a bloody hole in your target and dose them up besides.
Damage Modifier -2, AP modifier +2, Availability: (as chemical +2R), cost 200 nuyen.gif / 10 shots (plus chemical cost).
On a glitch the injection bullet disintegrates inside the gun, jamming it until it is stripped and cleaned (wear gloves!)

Ares Cobblestone
A pump action 'hunting' shotgun chambered in the same massive cartridge as the Enfield AS-7, the Cobblestone is popular among orc gangs and anyone looking for a heavy punch on a budget. At almost half the weight of the AS-7 the Cobblestone has a punishing recoil, but that has only made it more popular as a symbol of machismo.
Acc 4, Dam 13P, AP -1, Mode SS, RC - , Ammo 4 <c>, Avail 6R, Cost 600 nuyen.gif
Notes: For an extra 100 nuyen.gif the Cobblestone is available with a rifled barrel that increases accuracy by 1 but prevents firing flechette.

DIME Grenade
Designed to take down heavily-augmented targets while minimising collateral damage, a DIME (Dense Inert Metal Explosive) grenade consists of military explosive mixed with finely-powdered tungsten, cast into a lightweight carbon-fibre casing. The tungsten powder acts as micro-shrapnel, enabling very effective energy transfer to targets near the centre of the explosion but rapidly losing energy to air resistance as it travels.
Damage 18P, AP -4, Blast -3/m, Availability 14F, Cost 150 nuyen.gif

Feel free to post your own.