A clogged fuel filter will normally rear it's ugly head under higher fuel demand loads, such as while cruising on the freeway or hard acceleration, so I doubt that is the issue.
Your problem sounds very similar to what happened to our '92 camry last year. We were driving along and suddenly the engine felt like it was running on 5 cylinders instead of 6. The problem went away briefly, then came back. Then finally, it died while cruising around 50mph down a country road. The starter turned just fine but it would not fire. I checked the fuel pump (same test on the camry), and it worked. I checked the plugs, wires, cap, and rotor, and everything looked ok. I changed the plugs and wires for good measure, but no change. I then pulled the timing cover off and checked the timing belt, and it was fine. I pulled each plug, cranked the engine, and made sure I was getting spark to each cylinder, and I was. After checking several things several times, I finally went back to the distributor cap and rotor. The rotor had actually cracked! There was a hairline crack in it, and it was burnt around the crack (but it was hard to see). I put a new cap and rotor in, and it fired right up! I rechecked pulling a few plugs and checking for spark, and the spark was MUCH brighter with the new cap and rotor.
If you don't know how old your cap and rotor are, it would be a good time to replace them (only about $20). Plus, you should make sure the timing chain didn't break (bad), and to do this you can rotate the crank (3/4" bolt) and see if the distributor spins (it is supposed to).
