Well, it's reeeealy going to be subjective this one! (for instance, check out
http://www.fizik.it/spineconcept/ )
Can you give some idea of which type of saddles you've found comfortable/uncomfortable in the past?
That way it's easier to narrow down to thick/thin, narrow/wide, foam/gel, etc..
I personally like a flexy but thinly-padded, narrow saddle, and have found that the (old) Fizik Aliante is good all day long, and weighs not a lot..
Another really good alternative is to go for the lightweight varieties of Charge Spoon. The Spoon's pretty popular, can be got in 'plain' or retro-type colourings and seems comfortable for a wide (ahem..) variety of people. They come in at about 230-260g, depending on version.
The Fizik is 232g but the newer ones are a bit less weight, and a lot more cost. This is where the Spoon (around £25 quid for an alloy-railed one at 250g) is a good option without costing the earth, or your hindbones..
More 'modern' colouring is on the same saddle base (they're all Velos underneath) from Nukeproof, which are sometimes on sale for less than the Spoons.
You can go down to 195/210g for a (narrow) Selle Italia SLR, anything lighter than that & it's less a saddle & more a recurved seatpost topper.