I have a truly tight brass container that I keep in my console. When I want my fob to be invisible I drop it in and screw it tight. Say you want to go for a swim but don't want to take your $600 fob to the beach. You can make a plain metal key and take that. Drop your fob into the container and lock up. When you return use your metal key, which will allow you entry but will set off the alarm. Fetch your fob to turn the alarm off. It's not easy to find a suitable metal cylinder or box but I found one. Maybe an iron pipe with two caps would work but I wouldn't leave it in a visible spot. Maybe paint it pink too. A Hello Kitty sticker would make it look even less intimidating in a search situation. An ebay search for "brass container" got 2600 hits, some of which might be compact enough and tight against radio frequencies.