Here’s a MetaEfficient Keyring. It’s a collection of lightweight, mini-tools suitable for carrying on a keyring.

The keyring contains the following elements:

• The LD01 Flashlight by Fenix (powered by a hybrid rechargeable AAA battery)
• The folding waterproof Inka Pen
• The 6-in-1 Key Ring Tool by Swiss+Tech
• An Emergency Cash Holder by Cash Can

Here are the details of the MetaEfficient Keyring elements:

The LD01 Keyring Flashlight by Fenix

Fenix Keyring Flashlight Powered by AAA Battery

Why It Was Chosen

The Fenix LD01 is the brightest keyring-sized flashlight that runs on a standard AAA battery. This means it can be powered by a hybrid rechargeable AAA battery. It produces 80 lumens of light on its highest setting.

The Fenix LD01 uses a Cree Q5 LED as its light source, and the lens is made of toughened, anti-reflective glass. It weighs 1.6 ounces, and it is “IPX-8 water proof” meaning it is suitable for continuous submersion.

The flashlight is RoHS compliant (meaning it does not contain non-toxic heavy metals or flame retardants).

It’s available for $35 from Amazon.

The Inka Pen

Why It Was Chosen

The Inka Pen is a keyring sized ball-point that can be used quickly as a half-sized pen, or unfolded into a full-sized pen. Using a pressurized ink cartridge, the Inka Pen is waterproof and write at any altitude or temperature. It’s made in the U.S. and has a lifetime warranty.

The “6-in-1 Key Ring Tool” by Swiss Tech

Why It Was Chosen

The “6-in-1 Key Ring Tool” is a keyring-sized multitool by Swiss Tech. It contains the following:

• straight knife blade
• a serrated cutting surface
• a micro-sized screwdriver
• a Phillips screwdriver
• an eyeglass screwdriver
• bottle opener

The tool weighs 0.5 oz. Given its size, it’s pretty basic, its handy when you have nothing else available, but not suitable for everyday tasks.

The Mini Cash Can

The Mini Cash Can: A Keyring Sized Emergency Money Consealer

Why It Was Chosen

The Mini Cash Can is an emergency cash holder than fits on your keyring. You can secret a single bill inside this stealthy container. If you forget your wallet, you have the cash inside as a back-up. The Cash Can’s assembly cannot accidentally come apart as long as the keyring is through the hole. The container is waterproof.

I actually found a little difficult to fit a bill inside the Mini Can — the larger Mini II might be a better choice.

I’ve been testing the Vers 2x iPod speaker system. This system is one of the most energy efficient and sustainable products I’ve come across. The casing is crafted out of wood (either cherry, bamboo or walnut). The wood comes only from plantation forests, and each speaker system is hand-finished. This is a refreshing change from the usual dull plastic that is used to house electronics.

The Vers 2x is also RoHS compliant, which indicates that the electronics are free from particually hazardous components (lead, cadmium, mercury, hexavalent chromium, polybrominated biphenyl (PBB) and polybrominated diphenyl ether (PBDE) flame retardants).

The Vers 2x uses energy efficient components, such as a low-draw class D amplifier (see Class D Amplifiers Are Shrinking and Greening Your Electronics). I’ve tested it with a Kill-A-Watt electrical usage monitor, and the speakers draw 2-3 watts while playing music, while idle it draws virtually zero watts.

The Vers says the system uses 50% less than comparable products.

The sounds performance is good — the wood casing helps to produce bass tones, and the system can easily fill a room with music.

It also comes in 100% recycled packaging.

It’ss available from Amazon for $149 – 179.