Pewag
Offers snow chains, gear-lifting chains, and drive chains.
http://www.pewag.com

Zenax Chains
Zenax Chains - Manufacturers and Supplies of high-quality Standard Roller Chains, Stainless Steel Chains, Conveyor Chains, Agricultural Chains, Hollow Pin Chains, Double Pitch Chains, Attachment Chains, Leaf Chains, Slat Chains, Special Application Chains, and Spare Parts, India, USA, UK and all over the world.
http://www.zenaxchains.com

Drives & Drives
Roller Chains, Sprockets, Couplers, Conveyor Chains, Slat Chains, Backstops, Precision Roller Chains, Heavy Series Roller Chains, Straight Sided Plate Chains, Standard Chains, Double Pitch Chains, Mayr Products, India
http://www.ddrives.com

Double-double precision
Fortran 90 code by Claire Moreau-Finot for double-double precision arithmetic. That is about a hundred bits of precision with a floating point notation. The library computes the exponential function radix 2 and e, the cosine and the sine.
http://perso.ens-lyon.fr/marc.daumas/SoftArith/ddouble.php?langue=en

Peerless Chains Company
Tire chains, traction cables or snow chains are manufactured at Peerless Chain. We manufacture chain for retail outlets.
http://www.peerlesschain.com

Kool Key Chains
Mini carabiner style keychains..Key chains and links that clip onto anything.
http://www.geocities.com/koolkeychains/

FLEXON GmbH
Steel flat top chains -chains with straight or special-purpose link plates
http://www.flexon.de/

B & S Chains
B&S Chains specialises in spares to help you maintain your playground to a high standard at affordable prices. All our products conform to BS EN 1176/7., U BOLTS, EYEBOLTS, SLINGS, B&S CHAINS, SWING SEATS, SWING CHAINS, PLAYGROUND SPARES AND EQUIPMENT, Our company specialises in spares to help you maintain your playground to a high standard at affordable prices. All our products conform to BS EN 1176/7. We hold stocks of most items and offer a very prompt service. Should you require a product which is not on our web site or have any queries please contact us on 01384 413088
http://www.bandschains.co.uk/

Astronomical League Double Star Club
The purpose of the Double Star Club is to introduce observers to 100 of the finest double and multiple stars in the heavens.
http://www.astroleague.org/al/obsclubs/dblstar/dblstar1.html

High-Precision Software Directory
David Bailey's package for multiple precision, and packages for double-double (~32 dec. digits) and quad-double (~64 dec. digits) precision. The last two are in C++ with Fortran front ends.
http://crd.lbl.gov/~dhbailey/mpdist/mpdist.html