I've been thinking about buying a cheap tablet to muck around with installing desktop linux on, use android, and generally hack around with.

Has anyone got any experience with cheap tablets like the Kindle Fire? I'm thinking less than $300 USD, which cuts my options down a bit. Ideally the screen would be larger than the Kindle Fire, but if it is it'll probably be too expensive. I have no idea what's available.
CPU will need to be 1GHz dual core, and at least 512 MB RAM. Wifi is a must, 3G isn't. And it should be android.

http://slickdeals.net/f/3606564-Asus-16GB-10-1-Eee-Pad-Transformer-Google-Android-3-0-Based-Tablet-299-at-HHGREG-B-M-Only
wait around for this to come again. You probably want a keyboard, and this has a keyboard for $100 that has a battery in it.

hhgregg doesn't ship internationally (I'm in New Zealand) and that slickdeals site doesn't have great reviews of their service the tablet itself looks excellent, it's just a bit too pricey for now. I might just wait a year and see what happens to the prices; I'm in no urgent hurry to get one.

Or I could get a cheaper tablet...which will have a smaller screen probably and worse specs. Hrm.

Sorry for double post; I'd say this is a legitimate reason to though.

After looking around, I found this tablet: http://www.merimobiles.com/Zenithink_ZT280_C10_Zepad_C91_10_1_inch_p/meri2548.htm

It's got a 10.1 inch screen, 1GHZ CPU (unfortunately it's probably single core, I can't find anything indicating it being dual core), 512MB RAM, a USB port, runs android, and is very cheap. Hard drive storage is expandable via SD card, and I can't find anything wrong with it, other than one of the desktop modes looking pretty laggy (not a problem for me).

The other possible negative is it's Chinese, so the build quality may not be amazing. However, for the price I doubt I'd complain.

I'm still looking for alternatives but this is the best I've seen so far.

I'd be really really careful with those. I've watched reports in TV where they tested chinese tablets and they were all crap. Performance just wasn't what was advertised, case and ports were flimsy and support non-existent.
Though you never know, they could have tested the worst of the worst to spread the impression that all chinese products are crap, but personally I wouldn't take the risk from what I've seen.
Maybe reviews can help distinguish the good from the bad.

Yeah I've been doing more research into it and you have to be really careful. From the sounds of things that particular tablet is pretty decent in terms of build quality but that seller site I linked to is pretty horrible, although not an outright scam. Really bad shipping times, QA, and customer service. Next I have to work out how much shipping will be from other trustworthy stores and such. This could end up being a $300 lesson in being too trusting

A lot of times I've noticed people report those things a lot in reviews as being terrible, but it's usually the specific customer or only the worst experiences are the ones getting reviews. If you find a significant amount of positive reviews in such a case (and not really any middle ones), I think that means it's alright.
For example I ordered something recently from such a site where all the reviews said it took weeks and weeks, they received broken merchandise, and then there was nobody able to help them ... However, I got my shipment in 2 days (free shipping) and in perfect condition. (I used that site because the stuff I was getting was $15 cheaper than anywhere else, and half as much as a physical store.)

ASUS is Chinese, in case you haven't heard.

(Not like you will find any electronics that don't come from foxconn fabs one way or another...)

http://product.madeinchina.com/10-2-quot-cortex-a9-zenithink-ZT-280-C91-tablet-pc_13243884.shtml found a wholesaler who has it cheaper than anyone else, mostly good reviews (more than 900 positive, only 12 negative) and have had someone on a tablet forum recommend the buyer. I'll probably grab that one with a 16GB microSD card for another $23 USD, total of $250 NZD which is not bad at all for a tablet of those specs and reported build quality.

Have ordered from the seller linked above, here's hoping I didn't just make a USD$175 mistake

I forgot to update you guys, the tablet arrived and is excellent, considering it's only $175 USD. The screen is nice, it's fairly snappy, it came with ice cream sandwich, and is everything I was looking for. Minor problems are youtube videos not showing correctly, and I can't download music to the internal flash memory,although I should be able to fix that by messing around with mount points.