The bicycle rim has evolved a long way from wood and steel, and the aluminum used particularly during the 1970's, 80's, 90's, and 2000's is the best of what the sport has to offer.  Carbon fibre, on the other hand, is much more expensive than aluminum, and the braking performance of carbon fibre is sub-standard when compared to aluminum.

For these reasons, aluminum is the most prized material for tubular racing and training bicycle rims.  It is light and strong, and it is a relatively easy material with which to build wheels.  A lot is known about building wheels with aluminum rims and steel spokes.  And it is much more affordable than carbon fibre.

Trends are fickle though, and carbon is gaining a large following due in large part to exhaustive marketing by carbon manufacturers spineless coalescence from bicycle magazines.  But just as trends have been away from aluminum rims and towards carbon, aluminum tubular rims are becoming less and less available on the market.  This means that high quality aluminum tubular rims are more difficult to find, and it also means that they are more valuable.  Even 30-year old rims are selling for high prices on eBay.

Historically, the highest quality rims have been made by three European companies: Fiamme of Italy, Ambrosio of Italy, and Mavic of France.  The second two are still going strong.

Ambrosio continues to offer a lighter rim (the F20 Crono), a more durable rim (the Nemesis), and a more affordable rim (the Montreal).  Out of print Ambrosio rims include the Synthesis and the Metamorphisis (both similar to the current Nemesis), and the Futura (which is a strong and aero, but heavy, rim).

Mavic in 1999 or 2000 went from offering four or five aluminum tubular rims for individual sale to offering just one: the Reflex rim.  It is available in a polished aluminum version or a hard-anodized (CD) version.  Out of production Mavic rims include the GL 280 (so named for its weight of about 280 grams per rim), the GL 330 (about 330 grams per rim), and the Paris Roubaix SSC (a hard anodized and very durable rim, one that is still used on the Mavic neutral support motor-bikes at the Paris-Roubaix classic).

Fiamme is sadly out of business.  Their yellow-label rims were extremely light, and their red-label rims were extremely durable.

Rims from all three of these manufacturers tend to get a premium price on eBay, especially those that are out of production, for obvious reasons.  It is important to note that out of production rims have most often been taken off the market not because of some actual improvement in materials or breakthrough in engineering, but because of some lack of marketability or high cost of production.  Some of the best rims are no longer available.

These rims can be broken down into three categories.

First, there are basic rims made of polished aluminum.  Famed wheel-building expert Jobst Brandt says that polished aluminum is just as strong as hard anodized aluminum, and that the braking is better.  He also states that polished aluminum braking surfaces result in a more consistently strong rim than do machined braking surfaces.  All that aside, these rims can be durable, and they can be light.  Fiamme, for example, went a long, long time without ever hard anodizing a rim.  Other very good polished rims were made by Campagnolo, Araya, and Wolber (formerly Super Champion).

Second, there are rims that are (or were) made as light as possible.  These include the no-longer-made Mavic GL 280s and the GL 330s.  Both are somewhat less durable, and somewhat softer aluminum, than heavier and more durable Mavic rims.  And yet for certain applications (such as time trials, hillclimbs, and mountain-top road races), they are perfect.  Amborsio's F20 Crono is a hard-anodized rim (which defies my categories) that weighs around 360 grams per rim -- and it is still made.  Other such rims are the FIR SSC, the Vittoria Crono, and the Campagnolo Record Crono.  The Fiamme Ergal Yellow Label rim is one of that company's lighest ever rims.  Note that with lightweight, swaged or butted spokes (such as DT Revolution spokes), these rims can be made into wheels that are more dirable and often lighter than carbon-fibre wheelsets that sell for $2000 USD or upwards.

Lastly, there are rims that are hard anodized for durability.  Whether or not the anodization treatment really adds much durability is open for debate, and has been argued about for decades.  The aforementioned Jobst Brandt seemed to think that it does not add durabilty or strength.  But pro mechanics obviously tink it does since rims such as the Ambrosio Nemsis or Metamorphisis or the Mavis Paris Roubaix SSCs have appeared on the bikes the professionals race on in perhaps the world's most demanding bicycle race of all: Paris-Roubaix.  Other such rims include the Vittora CG rim, the Galli Paris Roubaix rim (let's be honest, rims makers were not creative with names, and most any rim named after the great race would have been built for its rigors), and Campagnolo Record Pave.

In terms of eBay values, Mavic rims have the strongest following and force the highest prices.  Campagnolo rims also have a strong following.  And yet as more obscure rim manufacturers become known (such Ambrosio, Fiamme, FIR, Galli, Wolber/Super-Champion, and Nisi), demand and prices for these rims may well increase.  Virtually any of these rims will compare favorably with some of the newer, mass-produced rims being made today by companies who came into the sport through the back-door, by importing Asian-made components and relabelling them.