Your arms are full of groceries as you approach your car, and you can't free anything to open the boot. What do you do?
If you drive a 2013 Mercedes-Benz SL, you just swipe your foot underneath the back bumper and, presto, it opens automatically.
It's just one of the new things that you get when you shell out the equivalent of R1 million or more for the newest luxury cars, all on display at the annual North American International Auto Show in Detroit.
While electronics advances and cheaper computer chips and memory have leveled the field for a lot of interior bells and whistles - GPS systems, blue-tooth capacity and smartphone connectivity are pretty widespread now - there are still some things you only get if you are ready to pay.
The SL, for instance, has a windshield cleaning system unlike any other. Instead of spraying a stream of often misdirected fluid on the windshield, risking splattering the passengers in the convertible, the fluid oozes from 40 holes in each wiper blade.
And several Mercedes-Benz models have its “air scarf” heating from the headrest, in addition to the now de-rigueur seat warmers found in your average sedan these days.
Porsche on the other hand has seat cooling. The brand new 911 S Carrera launched this week in Detroit will suck in air through the perforations in the seat and seat back to keep you dry in sweaty weather.
“For those times when you are wearing a suit on a hot, sticky summer day to go to a wedding,” says a Porsche official.
With engines equally powerful and leather interiors standard, carmakers have to compete increasingly on the looks, and the special bits that might not drive a buyers interest but can help seal the deal.
Little things such as Cadillac's illuminated door handles, which light up when the driver's key fob gets close. Or on the Bentley GTC, the seat belt automatically protrudes from its hiding place after you sit down, to make it easier to pull into place.
Porsche and Mercedes vie for speed records of a different kind: Mercedes says its convertible tops can open and close while the car is running at speeds up to 50km/h. Porsche claims a 55km/h capability in the new 911.
Most high-end cars at the show are offering new safety equipment, though not always standard, such as parking sensors and cameras.
Cadillac's newest models have sensors to tell if the driver is falling asleep and weaving out of their lane.
Errant driving will set off a flashing light in the car's mirrors, or there is a pulse in the seat to wake you up.
Cadillac also offers ‘virtual bumpers’ that at slow speeds will automatically brake the car if it is going to hit anything.
Porsches will also tell you, by a flashing light, if you are trying to change lanes when someone is in your blind spot.
The main battle for attention is in the capabilities of the LCD screen or screens on the dashboard that have grown to iPad size and capability.
Voice recognition is becoming standard, as well as customising the settings for different driver needs in the same vehicle. Cars are loading up on apps of all sorts, and gigabytes of memory for packing in everything on one's iPod, or tailored lists of favourites, destinations, radio stations or playlists.
In Cadillacs and Porsches, screens in front of the driver - where, traditionally, the gauges are - can show information such as driving maps or directions, when the main central screen is being used for other applications.
Cadillac's new instrument panel, soon to debut on its cars, is an all-LCD touchscreen interface, and information from the main screen can be dragged over from the central screen with a flick of the finger.
And the main screen goes back to the main menu when one's finger gets close, before you touch it.
Not to be outdone, Lexus has a 310mm screen in the GS to work with. Plug in your smartphone, and it offers apps with direct links to popular websites for finding fuel stations or restaurants, or buying tickets to concerts.
Centre-mounted touchscreens require a long reach. So Lexus has positioned a mouse-like creature - a clickable knob - on the centre armrest.
But some drivers won't want to be bothered to do the searching themselves. So Lexus offers owners a concierge service: you can call a representative to ask for any kind of assistance and they will look it up for you. It's free for the first year. - AFP