you can claim for electricity etc used with washing towels, also a percentage for use for when you are working on your biz. You would have to work out your own %, I personally don't but I keep on meaning to keep receipts for washing powder and keep on forgetting.
Yes, you can claim back a % of line rental and phone calls.
I didn't bother with the room use (even though I have a built in office) as I had heard it creates problems if you ever want to sell up.
I claim all of my mobile phone pay as you go back as I only bought the phone for work use.