Modern Days Communication

Everytime you went out, what would be the 'must bring' items?
Your wallet with money and I/C and your cellphone of course...
Everytime you wanna meet your friends at outside, will set the time and place properly and be there right in time and meet each other successfully?
For myself, i'd say NO. I'll keep calling or SMS-ing to make sure them to be there.
What if we happens to have no cellphone with us? Wouldn't it be such a trouble for us? Is it because we rely too much on the cellphone and consisted us to lost faith on each other?
I think so... Haha~
For an example, I went to pasar malam for a quick purchasing with my mom just now. Due the inconvenient for unable to look for a parking, My mom asked me to go buy the wanted stuff 1st(Air Soya bungkus 3). So I grab the money only, leaving my cellphone and wallet to my mom to avoid item dropping and dashed to the stall which selling Soya drinks.
After purchasing, I rushed back to spot where I get down from the car. I was glad to see the car was still there. But when I take a closer look, my mom and sis who suppose to be in the car just now went missing. Duh~
They've mentioned about buying something at Econsave just now, so I just went into Econsave for a look whether they're inside or not. I was intend to test how does people from past be able to contact each other without cellphone that time.
Anyhow, my experiment failed. I can't find them. =.= So i decide to wait them by the parking lot. I can't even tell how long I've waited for my cellphone wasn't with me. After a moment, they've back. I'm glad... and we head back to home.
Then my sis told me that they've wait for me for quite a time also in front of the entrance of the pasar malam. So, I've waited like a fool, and they waited like stupids just because my phone wasn't with me.
We can't live without cellphone don't we?