What is the most fuel efficient commuter?

[wested]

Hello, my commute may soon be increasing therefore I am attempting to work out what could be a suitable fuel efficient car for the commute of approx. 60 miles each way within a budget of under £2k.

So far, the Smart ForTwo and the VW Lupo come to mind with around 60+mpg.

Anymore suggestions?

[wested]

Mostly motorway miles with a smattering of A-roads.

Completely open to suggestions as to what type of car - but I'm guessing smaller would be better for mpg?

I guess even an lpg conversion could work but I really don't have any experience on what economy these cars are capable of?

[wested]

Thanks a lot for all the help guys!
You have given me a lot to think about.

The aim really is to find a car that costs very little (thereby limiting depreciation) and is as fuel efficient as possible to maximise range and keep costs down.
I have a sports-car to play with at the weekend so not too bothered about whether the daily commuter needs to be luxurious.
(Although any creature comforts really would be a bonus..)

The list so far stands at:

VW Lupo diesel
Smart ForTwo or roadster
Peugeot 206 1.4 hdi
VW Golf 1.9 TDi Bluemotion
Audi A2
Alfa Romeo 147 JTD