Linux kernel version you're running

There are many ways to find out as shown below. As can be seen here, I am running Linux kernel version 3 on my Ubuntu 11.10 installation.

suraj@suraj-Satellite-T135D:~$ uname -r
3.0.0-15-generic
suraj@suraj-Satellite-T135D:~$
suraj@suraj-Satellite-T135D:~$ more /proc/version
Linux version 3.0.0-15-generic (buildd@crested) (gcc version 4.6.1 (Ubuntu/Linaro 4.6.1-9ubuntu3) ) #26-Ubuntu SMP Fri Jan 20 1
7:23:00 UTC 2012
suraj@suraj-Satellite-T135D:~$
suraj@suraj-Satellite-T135D:~$ dmesg | grep Linux
[    0.000000] Linux version 3.0.0-15-generic (buildd@crested) (gcc version 4.6.1 (Ubuntu/Linaro 4.6.1-9ubuntu3) ) #26-Ubuntu SMP Fri Jan 20 17:23:00 UTC 2012 (Ubuntu 3.0.0-15.26-generic 3.0.13)
[    0.182604] [Firmware Bug]: ACPI: BIOS _OSI(Linux) query ignored
[    0.656368] Linux agpgart interface v0.103
[   19.260366] Linux video capture interface: v2.00
suraj@suraj-Satellite-T135D:~$
suraj@suraj-Satellite-T135D:~$ ls /boot
abi-3.0.0-12-generic     config-3.0.0-15-generic      memtest86+_multiboot.bin     vmcoreinfo-3.0.0-14-generic
abi-3.0.0-13-generic     grub                         System.map-3.0.0-12-generic  vmcoreinfo-3.0.0-15-generic
abi-3.0.0-14-generic     initrd.img-3.0.0-12-generic  System.map-3.0.0-13-generic  vmlinuz-3.0.0-12-generic
abi-3.0.0-15-generic     initrd.img-3.0.0-13-generic  System.map-3.0.0-14-generic  vmlinuz-3.0.0-13-generic
config-3.0.0-12-generic  initrd.img-3.0.0-14-generic  System.map-3.0.0-15-generic  vmlinuz-3.0.0-14-generic
config-3.0.0-13-generic  initrd.img-3.0.0-15-generic  vmcoreinfo-3.0.0-12-generic  vmlinuz-3.0.0-15-generic
config-3.0.0-14-generic  memtest86+.bin               vmcoreinfo-3.0.0-13-generic
suraj@suraj-Satellite-T135D:~$