BODILY INJURY LIABILITY COVERAGE
"This coverage pays damages due to bodily injury to others for which you are responsible. If you are sued, it also pays your defense and court costs. Medical expenses, pain and suffering, and lost wages are some examples of bodily injury damages."
This is one type of coverage where I feel it pays to pay. The coverage gets incredibly cheaper per dollar of premium as you approach the upper limits of this policy. Additionally, top-tier limits are usually required for an umbrella policy. As most of the damages that you could be held liable for in an auto accident are for medicals, not property damage, this is where you want to really take care of yourself.
PROPERTY DAMAGE LIABILITY COVERAGE
"This coverage pays damages due to property damage to others for which you are responsible. If you are sued, it also pays your defense and court costs. Property damage includes damaged property and loss of its use."
I think $50,000-100,000 is the upper limit of what you should reasonably be paying, even though additional coverage is so cheap. The cheaper the additional coverage, the less likely you are to ever need it. Most accidents are going to be with one car, and unless you crash into a Ferrari I don't see how more than $100,000 in coverage is ever going to benefit you.
UNINSURED MOTOR VEHICLE COVERAGE - BODILY INJURY
"This coverage pays damages for bodily injury when an insured is injured in a car accident caused by another person who does not have any liability insurance or who has liability insurance, but whose available limits are less than the limits you chose for this coverage."
This is probably the most important type of coverage you can have IMO. I have done some insurance work, and I have seen this type of policy used many, many times. You have to remember that in many areas, up to 30% of all drivers are uninsured... so without this coverage you're insuring yourself against only 70% of all accidents AT BEST. This type of coverage will pay in case of a hit-and-run, which is all too common. Additionally, it can cover you or a minor child in your household if you are hit on the street by a motor vehicle, which is a real danger.
COMPREHENSIVE COVERAGE
"This coverage pays for a covered car that is stolen or damaged by causes other than collision or upset. For example, damage caused by fire, wind, hail, or glass breakage is covered. Collision with birds or animals is also covered. Comprehensive Coverage will also pay substitute transportation expenses of up to $16 a day if your car is stolen. Payments will be made starting 48 hours after the theft is reported to us. A deductible is not required."
This is pretty self-explanatory, higher deductibles will result in lower premiums... but not drastically so. If your car is worth close to nothing, or you are willing to self-insure, you may want to opt out of this type of coverage. PROTIP: Do not report minor windshield cracks, as you will end up saving almost nothing and end up with a mark on your insurance report, however slight.
COLLISION COVERAGE
"This coverage pays for a covered car that is damaged by collision with another object or by upset of the car. A deductible is required."
Same as above.
UNINSURED MOTOR VEHICLE - PROPERTY DAMAGE
"This coverage pays for property damage to your car if it is damaged in a car accident caused by an uninsured driver. If you have Collision Coverage, this coverage pays damages up to the amount of your Collision Coverage deductible. If you do not have Collision Coverage, this coverage pays damages up to $3,500."
So cheap, it's almost a gimmie.
CAR RENTAL AND TRAVEL EXPENSES COVERAGE
"This coverage pays for the following expenses: Car Rental Expense - Pays the amount shown below (six coverage options are available) when you rent a car while your car is not drivable due to a covered comprehensive or collision loss. It will pay $10 a day for each complete 24-hour period that your car is not drivable if you do not rent a car. Rental Car - Repayment of Deductible Amount Expense. Pays the deductible you may be responsible for if you have an accident in a rental car. Travel Expenses - Pays extra expenses for meals, lodging, and transportation home or on to your destination if a loss occurs more than 50 miles from home. It also pays for the trip to pick up the car.."
Car rental companies give a highly-discounted "insurance" rate. $25/day should be more than enough to get you a decent set of wheels. May not be needed if you can get around for a week or two without a car.
MEDICAL PAYMENTS
"This coverage pays medical and funeral expenses for bodily injury to a covered person sustained in a car accident. Medical expenses must be reasonable, necessary, and for services furnished within three years after the accident. The most we will pay for funeral expenses is the lower of your limit or $3,000."
If you have health insurance, why bother... unless you have a high deductible for your health insurance.
EMERGENCY ROAD SERVICE COVERAGE
"This coverage pays the reasonable expense for the following emergency services for your car:Mechanical labor up to one hour at the place of its breakdown. Towing to the nearest place where repairs can be made during regular business hours. Towing the car if it is stuck on or next to a public highway. Delivery of gas, oil, loaned battery, or change of tire, but not the cost of such items. Locksmith labor for up to one hour if you lose your key or lock it in your car."
May want to avoid. Service calls can show up on your CLUE report and have an adverse affect on your rates and insurability. May want to look at AAA or similar programs.
Note: I am working on this because I will obsessively tinker with my policy to try and get the best deal and the best coverage, so I will edit this as needed with new information as it is provided.
All input is welcome!