25K - RMS (under warranty)
~80K - AOS
~90K - rear wheel bearing
~100K - couple of O2 sensors
<150K - cracked rear window
172K - water pump
<200K - MAF
<200K - AOS (2nd one)
~220K - fuel pump
~240K - coolant tank
<250K - VarioCam solenoid/sensor
~250K - CV boots (bearings cleaned and repacked and reused)
<280K - replaced original converters with used ones (one original had a loose brick)
There have been some door lock, door latch and window regulators along the way. I do not recall the miles now, but all have been after 200K miles.There's been a clutch interlock switch, a brake light switch, and an ignition switch too. Oh, a coolant tank cap and an oil tube filler cap.
Oil/filter is done every 5K miles. Other vital fluids are changed on schedule or if not then done early. For instance, most of the time I have the 5-speed tranny fluid changed at less than 90K miles. Brake/clutch fluid flush/bleed every 2 years. (Well, recently I had an experience where I let this go for 2.5 years and while the braking was unaffected clutch action/shifting was degraded quite obviously but thankfully recovered completely after the brake/clutch fluid was flushed and bled.)
Plugs are done based on miles. Serpentine belt, ditto. Engine air filter, cabin air filter, done every other year. Coolant drained and refilled every 4 to 5 years. I would have done this regardless, but it so happens the 1st one came about after I ruined a radiator hitting some road debris. The 2nd change came about when I had the water pump replaced. The 3rd one came about when I had the coolant tank replaced. There is no serviceable fuel filter. It is part of the fuel pump housing.
I can't recall how many miles I get from the brakes. But I do know that brake life varies considerably and given my driving usage is consistent and my driving style is consistent too I have to attribute it to differences in the pad/rotor material. Some pads seem harder and rotors softer than at other times I buy the brake hardware. As near as I can tell with the longer wearing hardware present or with the shorter wearing hardware present braking action and feel is unaffected. Braking is still, and always has been, superb. One clue as what kind of brake life I'm going to get is the amount of brake dust. When I see the wheels black with dust in just a day or two after washing the wheels I'm pretty confident brake life will be shorter than it would be otherwise. This set of front brakes appears to be based on the brake dust a set of the shorter lived hardware. The previous set was the longer wearing hardware.
Rear tires last easy 20K miles, fronts double that. Alignment done only if tire wear patterns indicate alignment issues (or if dealer has a $100 special on alignment when I get 4 new tires installed). As for tire wear patterns, for instance, if there is inner edge wear on the rear tires that's a cue for an alignment. With a proper alignment and with strictly street driving rear (and front) tire wear is even across the tread face. The front tires on the Boxster have never shown any wear signs of being out of alignment.
Oh, I forgot. Some plastic trim. For instance, the plastic strip that runs along the base of the windshield was replaced after it cracked due to age/exposure. A few underbody panels that something kicked up under the car damaged to the point the panels were no longer secure. Drop links of the front sway bar. A dust cover cracked and I had the links replaced. Which reminds me the windshield was replaced after a rock chip developed over a year or two into a huge crack that extended across the full width of the glass at eye height. However, I can't remember at what miles or when this was done. There have been several batteries: The original one (Moll) lasted 6+ years. Its replacement, also a Moll, less than 2 years. The 3rd battery -- Interstate -- appears to be holding up well. (As an aside a replacement Interstate battery in my 996 lasted just 7 months. Thankfully its replacement, also an Interstate has beaten that and appears to be going to last a reasonable amount of time.)
Current mileage? Well, I filled up the fuel tank on the 20th and the mileage then was 281726 miles.