hmmm, let's see... (pictures aren't of my items, but examples of what they look like)
A katadyn combi plus filter,
an MSR Mioxx,
and a camelbak hydrolink in line filter made by MSR.
Of course having some purification tablets, the ability to boil water if needed, etc are always good and backups to the above systems. I don't use all three together, but have all three for when they're needed. For home use for everyday tap water I use a brita maxtra. The filters we get here are German made, I'm going to assume the maxtra is offered in the states.
The berkey's are nice. One of my family members uses their's everyday to filter their well water.
Another neat option would be the filter at Monolithic Marketplace — Just Water, Ceramic Drip-Filter
Having the ability to have clean, pure water is very important.