This could come in handy

[naidib04]

http://www.target.com/OpenZoomLayer?template=scene7-image&image=Target/10895110_is&swCellSpacing=10,10&swHighlightThickness=1&swBorderThickness=0&itemTitle=Wagan 900-Amp Battery Jumper with Air Compressor

Just browsing around and came across this. Would be useful if you don't want full OBA.

[hoaxci5]

I have one from harbor freight, while it will work to inflate a tire, you would be waiting for a long time. For sure not ideal for air up/down situations, but great as an emergency tool.

[Matt]

I wouldn't consider that for OBA at all... who knows what that pumps even rated it. I've seen things like that take 20+ minutes just to get a normal car tire back up to pressure.

If you want to spend under $100 for OBA, something like this would be a bit more applicable:
http://www.viaircorp.com/OffRoad/90P.html
http://www.amazon.com/Viair-93-VIAIR-Portable-Compressor/dp/B001MXL71A/ref=sr_1_3?s=automotive&ie=UTF8&qid=1326492731&sr=1-3


That way you at least know what kind of pump and ratings to expect.

[naidib04]

Yeah I was thinking that for an emergency situation it would be useful.

[Holaday07 4.7]

We have one of those kind of. Paid $20 for it. We use it for pool toys, air matresses when camping, and in a real emergency it could fill a tire. Only goes to 240 psi and would probably take an hour to fill a tire.