I hope this isn't a stupid question...
 

Is Windex safe for the clear-coat on a new RX-8? I had some nasty spots (like grease+sap?) on the hood, and they came off fine but left smudges... so I took out some trusty Windex and it looks brilliant again. Using a soft cotton paper towel (yea, good paper towels, not scratchy ones) and some very light spraying I got the spots off the hood.

Was that a bad idea? I'm not coating it or nothing, just a light spritz where needed to wipe off crap.

The windex should be fine. My suggestion though is to use an automotive bug+tar cleaner, or my favorite - Meguiar Spray 'n Shine (I think that's the name) so it doesn't strip off your wax.

I respect your wish to get the crap off ASAP, but you really need to carry a good quick detailer spray and some microfiber towels with you for this sort of emergency. If you already have a good wax base, the QD will whisk the crap off and enhance (not damage the shine.

OK, so I'm open for recommendations as to what to carry in an "In case of emergency" clean-up kit.

What he said

yup...exactly that...

and windex is bad for just about everything but plain boring windows...just please don't use it on tinted windows...such a mistake that just about everyone makes..

windex = not so good for automotive surfaces

get Meguiar's Quick Detailer and use that to clean up most minor mess on your car :D

and Stoner Invisible Glass for cleaning the glasses, did i mention it's tint-safe? :D

i use it on the OUTSIDE glass of the car if I have nothing else left....but dont get it on the paint or on the inside of the glass. Use an auto-glass cleaner for that.

I also wouldnt use anything buy microfiber on the car...no newspaper/paper towels

I agree with the microfiber, I carry one and a bottle of "Speed Shine" from Griot's Garage (mail order/online). I also like to use the Griot's car wash, used straight it removes road tar, bugs, and sap without damaging the paint. They have a lot of good detailing products.

You should rewax the area that you cleaned with the windex. It most likely stripped your wax off.

use clay bar.. it removes everything without any damage.... every those bumpy tree sap that can't be removed by washing ur car....

And here after watching "My Big Fat Greek Wedding" I though Windex was good for everything.

I agree about Meguiar's on the car surface. Best line of car products I've seen. On the other hand, I don't go crazy if I use Windex to clean the windows, and a little gets on the surrounding paint. After all, there are bigger things to worry about in life.

I love Griot's Speed shine, that is my fav product