Yes or no? And what would you buy them?
Definitely. I have given my two best friends sex toys. I have given vibes, bullets, lube, tenga eggs, cock rings, massage candles, etc, etc.
They were very happy to receive ;)
i have bought a sex toy for friends...neice (at her request) and a secret santa at work lol
I've given a few friends sex toys, lubes ect. All been well recieved Think you just have to gauge them, you know them best!
Only last week I made up a little parcel of a bullet and some lubes and gave it to a friend for her birthday. Was well recieved 
Yes -- I've done it before (at least, a vibrator as a birthday present in response to a hint that I picked up).
I'd suggest that it's rather important that, before going ahead, you have a good idea how it's likely to be received (not just by the recipient, but by their OH and your OH, if appropriate). In my case, this was fine all round, and I received a little thank you note to say, cutely, that the gift had been appreciated and did the job successfully.
I've bought 3 of my friends sex toys, 2 of those were birthday presents. I bought 2 I rub my duckies - the original and mini and the love bunny which has now been discontinued. The friend I bought the bunny for told me she loves it, it's cute and she already has a vibrator anyway. I'd say if you're not sure how they feel about sex toys then get them something that doesn't scream 'I'M A VIBRATOR' and could be passed as a massager.
I'd say go for it, I am so buying more sex toys as presents this christmas
I was once given penis shaped biscuits as a secret santa gift from a work colleague. It was quite funny but to be honest I was at the time more worried about my mum's reaction as she knew I was in the secret santa so I couldn't really hide them. Fortunately she saw the funny side too. That's the closest I've got.
Me and my friends usually make it a general rule that what we buy for each other HAS to be sexual. I can think of a couple of friends getting presents direct from here this year!