White One Seal and Bond Tub and Tile Sealant from Loctite provide a water tight, crack proof and scrub resistant seal around sinks.
Friends don't let friends tile counter tops. Everything Old is New Again: Tile Countertops, Then and Now
You can add a cork backing to the entire back of your coaster. These pads are available on Ebay.
The sealant I have found to be working well for the tiles is Krylon Triple Thick Crystal Glaze. I may use several coats.
How to Make Coasters - Warning! Read this before you make ceramic tile coasters
I'm pinning this for the sealant...because it's pretty cool!
Use to seal things after using mod podge
how to seal grout so it doesn't get mildew-y and keeps water out. it needs to be done a 2nd time about 6 months after the first seal. wish i had known that :(
How to restore dirty tile grout! This is so great! You simply use this grout paint and it only costs $10. Comes with a sealant so you don't have to scrub it to clean it later.