Screws onto the tap so the sprinkler or drip line turns itself off, and nobody comes back to a flooded bed. The Australian Neta and US Orbit timers are programmable, so they water on a schedule while you're away. The UK Hozelock is a simpler wind-up dial that switches off after up to 120 minutes.
An outdoor sensor sends rainfall, wind, temperature and humidity to a screen inside, so they can check the overnight rain with a cuppa instead of walking out to the gauge. All three measure rain and wind; the US Ambient Weather one also connects to Wi-Fi and an app.
AU For shoppers in Australia
Digitech Digital Weather Station with Monochrome Display clear LCD screen
Useful and decorative at once. The Australian one has a wren perched on a stake; the US one is a spiral with numbers magnified by the glass. The UK stake gauge is hand-blown glass on copper, and the shop says it's a rough visual guide rather than an exact measure.