It's kind of frustrating to have to "estimate" how many miles one has after the range reaches zero -- I keep track of my fill ups pretty carefully on Google Docs (even created a form =D) and I use the odometer reading from the previous fill up and the average MPG reading from the car (I also reset mileage for each tank) to estimate my actual remaining range:
Conservative estimate of actual range
= (ACTUAL RANGE WITH FULL CAPACITY) - (DISTANCE TRAVELED SINCE FILL)
= (23.5 gallons * MPG from car) - (Odometer Reading Now - Odometer Reading @ Last Fill)
Estimate of remaining fuel
= (TANK CAPACITY) - (FUEL USED)
= 24 - (Odometer Reading Now - Odometer Reading @ Last Fill)/(MPG from car)
It would be SO much easier to have an ACCURATE and precise range indicator -- the indicator may be precise, but again, we don't know to what value (e.g., how many miles can be driven after range = 0). You may think you have more fuel than you actually do with the range estimator being off so much.
The low-fuel light's a fine early warning, but I don't need Toyota to "trick" me in to getting gas early with an inaccurate range. If I see I have an ACTUAL 100 mile range, I can use Google Maps to figure out the nearest gas station within 100 miles and know confidently that I can get there. Understandably, fuel efficiency changes when driving, but the range should be a function of the actual remaining fuel left: not a function of the remaining fuel subtract 3 to 5 gallons. FWIW, I've gone ~60 miles after range 0 after I convinced myself that I still had 4.5 gallons left (conservative estimate assuming 23.5 gal tank). When I got to the gas station, I filled 22.04 gallons.
It's bothersome (and now I know not only to me!

) to see a 350 mi range when you know you're supposed to get 468 +/- 60 miles @ 24 gallon capacity 17 city/22 hwy. Even with 23 gallons @ 17MPG, range should be up at 391.