I'm a little tired of having a drawer of supplements, you know? I like the idea of many synergistic things being combined in as few containers as possible. That's why it takes me ages to find a pre-workout I like and why I generally have a tub of Ergonine or something akin to that kicking around.
What are your favorite all-in-ones that are reasonably cost-effective?
It depends on what you're looking for. There's not going to be any all-in-one for every possible goal.
For just your ergogenic staples (creatine, betaine, etc) Ergonine, PowerMax XT, and Triumph are all good options with a few differences between them.
For nootropics, I think NootropiMax is a good all-in-one type supplement where you don't have to add anything to have a pretty well-rounded "stack," and actually does have some proven synergistic ingredients like you mentioned in your OP.
There are a few good options for joint support if that's something you're interested in as well.
For a "test-booster," or something that can help with mood, libido, and a bit with performance, AlphaMax XT and M-Test are both solid and comprehensive formulas.
There are a good number of supplements that are basically "all-in-ones" for a given goal/use/purpose/etc, but nothing is going to cover, say, strength, memory, joint support, and sleep quality all-in-one and do a good job at any of them, so you may still have a few to several supplements, but that's still a lot easier than a few dozen when you're buying every ingredient separately.
