This topic from Long and Short Reviews took some thinking about. I have a lot of things which are important to me, but what couldn't I live without? As a writer, a few things stood out straight away.
First off - my computer. The source of all my information for my stories (with the possible exception of my phone) and also the location of all my WIPs. I'd be lost without it.
Secondly - notebooks for writing. Whenever I have an unexpected idea I write it down, and when I'm working on something new I use them for planning.
The third item is my Kindle. I always have at least four books on the go at any one time and many more samples saved for the future, particularly as I'm working my way through classic American literature at the moment.
Then a little less serious - wine.
My favourite is Torrontes, but I can't resist a fun label, as you can see here.
And finally - my cats.
Dash and Spot are always available to be stroked whenever I'm struggling with a plot point.
So what couldn't you live without?