I have the DELL Latitude X1 with 2GB DDR2 memory since 2005.
This one is light and small.
Further more,it's tough, I once dropped down on the floor,
but no damage.
I installed the 32GB SSD module on my X1 instead of HDD.
The SSD module is KingSpec KSD-CF18.1-032MJ that is available
in the ebay, etc. I obtained from the ebay store with almost 140 US dollars.
This modification made my X1 extremely quiet because it has no fans,
and speed up especially on reading data.
I will still use this X1 for a few years.