Depends a little on the particular type of riding... I've tried a bunch, and settled on ProLink as my favorite for general conditions.  It seems to persist fairly well w/o having to re-apply every couple rides, and it doesn't attract too much grit/gunk.  For my winter bikes, though, I'll still use something heavier/stickier like Finish Line Cross Country so it doesn't wash off as quickly in the rain (or even Phil's Tenacious Oil if it's really pissing).

I am out here in the dry desert of Arizona, have been using White Lightning, would like to try another.

I've tried a ton of them and ProLink Gold is by far the best for general dry riding conditions.  Drivetrain stays so much cleaner with it!

I like Prolink the best of all lubes because its light and doesnt attract dirt. I have recently started using Finish Line Ceramic synthetic lube and noticed it really quiets the drive train down and seems to last. Another good brand is Dumonde light and heavy versions.

I have settled on White Lightning.  I think it keeps the chain very clean.  Every week I rub all the old off as best as I can and then put a fresh drop on each link.  Make sure to shake the bottle beforehand as it separates over time.

I have used prolink and I don't get people who say it is clean.  It was a black, smudgie mess!  It was a revalation going from it to white lightning.

 Nate

Have tried most of them and Pro Link gets the nod. Drop onto the inside of the chain links and rotate the chain over the clean cassette. Wipe the excess off. On the next ride it may seem a little noisy for abot 30 seconds, but then the links get working and it is noiseless and smooth

I'm a big fan of Purple Extreme myself. It's quite thin and needs reapplication relatively frequently, but it doesn't attract dirt and keeps the drivetrain clean.

I live in Singapore.  Heavy tropical downpours are common place, particularly during rainy season.  Any further suggestions for the most appropriate lube for this environment?

Since this post started I got some Rock 'n Roll and that stuff is the best!!!  I never thought about the chain lube until I saw the post.  The White Lightning was good but this stuff makes the bike silent!

I have totally switched to Rock and Roll.

Once I tried it I was amazed how clean everything was, and how smooth it ran :)

ProLink gets my vote.

Phil