What are your favorite add-ons, accessories, retrofits, etc?

Tinted windows, spoiler lip, rear spacers, blacked out side marker light and rear "Porsche" emblem, ALP laser shifters, dash cam, wraped interior trim to body color, wrapped key with extra wrap material. Yeah I like to tinker.

I purchased the front trunk liner, rear trunk liner, cargo net, Porsche black rubber mats....all of which fit quite nicely plus Porsche valve caps, black LED side markers, Porsche battery maintainer, and Genius boost (if needed down the road). Also purchased a Uniden R3 detector but not happy probably going to return since it is much too noisy with all the false alarms.

Having nearly 4,000 miles on my Cayman now after only about 7 weeks of ownership, I feel like I can chime in on this.

These I consider must-dos:
- AWE Tuning Wind Foiler. Eliminates the nasty buffeting that happens about about 50 mph when one window is open.
- EU-spec clear front side markers. Cleans up the look of the front end dramatically.
- Tint windows. This is climate-specific, though anyone with leather on the interior should do this out of a matter of course to help preserve it.
- SD cards of up to 128GB each for music storage. Be sure to buy ones that are proven to work in a wide temperature range; I recommend either Sandisk or Lexar. This is one of genius things about PCM4, which can handle every widely used digital music file format except .aiff and Ogg Vorbis. With good programming, even the base sound system sounds pretty darn good (though I'll be upgrading that soon.)
- Compile a basic tool kit. Include some basic metric tools, a driver and Torx/flat/Philips sockets, flat-head and needlenose pliers, and a few other things, as well as duct tape, JB Weld, high tinsile-strength rope, temperature-resistant neoprene gloves, and a magnetic work/emergency light.
- Microfiber towels. Keep at least five in the car at all times; four in the back and one in the cabin. You never know when you'll need one: gas spill, bird droppings, garbage truck splash, random unknown-substance splatters ...
- First Aid kit. This one is outstanding.

As for some of the other things:
- The OEM Cargo Net is utter crap. It stretches out, only attaches to the D-rings by non-closing plastic hooks, snags very easily, and costs way, way too much for what it is. I have not found a suitable aftermarket equivalent, but I will keep looking.
- If you take road trips, I highly recommend obtaining (if you haven't done so already) a domestic carry on-size suitcase for the frunk (it fits almost perfectly; keep the thickness under 9 inches or so and you can stack two in the frunk) and a duffel bag for the rear that measures no more than 14 inches wide by 12 inches deep.
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