Must be.:
Inexpensive ( relative I know )
Fairly durable/ rugged
able to fit comfortably into a camelback
easy to get on and of the valves

Lezyne Alloy Drive.

Airwave motion mini pump.
Like a miniature track pump. Brilliant.

crc link

Topeak morph fits in bag slightly large , but makes inflating easy , really good I got fed up with smaller pump taking a year to blow up . Amazon £21

Blackburn, light and pumps quick/easy – only Presta if this is a problem

http://www.ukbikestore.co.uk/product/86/airstick_sl/blackburn-airstik-sl.html

I’ve a Blackburn MTN Shorty (the original alloy one) which has been on my bikes/in my camelbak for 12 years now & it still works fine.

Blackburn Mammoth is a good pump and sits nicely in my camelbak. Can be found for a tenner which is a bargain I think.

forget about the rest….go for a Blackburn Mammoth.

Topeak Mountain Morph (or the Lezyne copy)

Mountain Morph for me too. Pumps tyres up quickly and easily, well worth the extra size. I’ve had three Blackburns fall apart while in use. They worked well when they worked but not great build quality so I now avoid them.

Topeak Mountain Morph (or the Lezyne or madison copies)

Lezyne alloy drive. Tough and reliable

I’m going to get lambasted for this but…. Decathlon mini pump is about. 5 quid and is ace. Pretty small, pretty light, fits both Presta and schrader valves and blows tyres up surprisingly quickly.

+1 for Lezyne alloy drive. Quality pump

Lezyne Alloy Drive.

Years later, yep, it just works, and works.

Mountain Morph for me too…little bleeder turns into a mini-track pump and pumps up just as rapido too 😀 No contest fella, Mountain Morph yersen up.

Seems like its a toss up between the Top peak Mountain morph & The Alloy drive from Lezyne.

Thanks peeps..looks like the price will decide between the two…

Just got one of these to replace my Topeak Mini Dual G (was leaking round the o-rings)

http://www.evanscycles.com/products/bontrager/air-support-mini-pump-ec017727