Advice Needed from Mac Nerds

I’ve unearthed another old Apple device, this time at a computer repair shop here in Northern Thailand. The hardware looks brand new and it booted quickly with the graphics looking bright and sharp after booting.

iMax 20 inch Mid 2007.
Processor 2GHz Intel Core 2 Duo. Memory 4 GB 667 MHz DDR2. Graphics ATI Radeon HD 2400 XT 126 MB. 1 TB HDD.

OS X El Capitan version 10.11.3.

I asked whether the OS could be upgraded and the answer was No.

Has Apple succeeded in making this machine totally obsolete? Any advice about any ways it could be useful?