Hardly a recipe goes by in my kitchen without me squeezing in a little lemon juice at the end.
Along with testing for salt, the thing that can really bring a dish together and makes it sing - er, zing! - is a bit of lemon juice. Just that hint of acidity can coalesce flavors and take a dish from eh to oh yeah.
Of course, there are many recipes that call for more than just a simple squeeze of lemon juice. Sometimes whole lemons are called for, and I actually need to pull out my liquid measuring cup and squeeze my way through a couple at a time.
My favorite juicer for the job is the Chef'n Citrus Juicer ($20).
This thing is a tank: hefty, solid, and most importantly when it comes to handheld citrus juicers, it takes minimal effort to get maximum results. I don't have to squeeze the life out of this thing to get it to work! It basically does the job for me with limited pressure. The well has star-shaped slits at the bottom, which seems better at preventing seeds from getting through, and it's made out of nylon-coated stainless steel that seems indestructible, even after multiple cleanings in the dishwasher.
The only downside might be that it's a bit bulky, but given how well it works and how durable it is, I'll gladly continue giving up some of my drawer space for it.