I was ill in bed and the pain, suffering and noise was all just getting too much and I remember thinking "I can't take anymore," and gave up.
Suddenly I'm floating in this lit grey volume (lovely colour of grey) in complete bliss (the word bliss doesn't even come close to the feeling) and thinking "I'm at peace." Then I thought "well, if this is death, it's brilliant."
I could see a tunnel down the far end of the volume and decided to explore, so I went floating off down the tunnel. This huge steel gate suddenly slammed down in front of me (it had rivets and straps and the intention of making the point "make no mistake matey, this is a big steel gate. Get lost."
Next thing, I'm back in the pain and suffering and I thought "sod this." I found myself back in the volume floating about, so I headed for the tunnel again and when I charged up toward it, the steel gate shot down blocking me and I was back in bed. While I was out-of body, a doctor looked at my monitor and said "That bloke's had a coronary."
I had a very serious condition, with my blood pressure fluctuating wildly, treatment needed, and recovered (over a long period) IN SPITE of the doctors.
I learned what people mean when they say "He's at peace now" at funerals, and can give some comfort to relatives of those who have passed by telling them briefly of my experience (sometimes the only crumb they have to cling to).
I'm an atheist and don't care about life or no life after death. However I can assure you that 5 minutes after you die you will not be sitting there going "Rats, there is no life after death."