Aldi (UK) has a cheap 30W soldering iron on sale from Sunday. Its not the best in the world but at £6.99 it's cheap enough to keep as a spare
http://www.aldi.co.uk/uk/html/offers/special_buys3_21520.htm
If that doesn't float your boat, they have a Helping Hands clamp and magnifying glass for £2.99
http://www.aldi.co.uk/uk/html/offers/special_buys3_21521.htm
What the ??!@#!
I thought Aldi only sells cheap food. Last time I picked up a roll of food wrap at aldi and still have half a roll. Cutting blade is cheap dull plastic and I have to rip hard every time. Just check their US website, yep, just food and some kitchen stuff.
Aldi and Lidl here in the UK, always have something interesting for the DIY'er of the house to browse and stick into the shopping trolley. I nearly always end up with a set of something, spanners, screwdrivers - you get the picture 
Interestingly, Lidl (UK) have a nice looking magnifying glass with clamps and soldering iron holder for £4.99:
http://www.lidl.co.uk/cps/rde/xchg/lidl_uk/hs.xsl/index_25486.htm
Every now and then the Lidl/Aldi in my neighbourhood also sells tools, microwave ovens, radios, computers and even bicycles. Some of those are quite interesting given the price.
I did buy a solder-iron at Lidl once, but I'll never do that again.
While soldering just one board (with quite a number of components) the tip, new, dissolved half.
After that I've assembled PCBs at a firm for two years with professional equipment, have assembled/corrected at least 10.000 boards and... used two tips in total ! Tips used just started to degrade.
Nowadays I use an old iron I got while working at the assembly-firm. Before the Lidl-one I used a cheap Weller for about 15 years, unfortunately the tip also started dissolving after many years of use. Since the tip corroded in the iron as well I can't replace it any more although I can still buy spare tips for it.
So, If I had to buy a new one for a few bucks I'd probably spend 2-3 times the money of an Lidl/Aldi-one,
buy a weller again and take better care of it.
Too little plating (chromium?) on the tip? I bought a radio shack 8USD kit and the tip gets eaten away quickly if you leave it plugged in between securing parts on a PCB. The 30W power is too large for the tip. 20W would be probably better. Plus, mine is still fine but those ones I bought for students got their tips eaten up
I also have weller battery-powered irons. Their tips are pristine even after around 1,000 solder points. I suspect low power + good plating. Just too much hassle to replace battery every 200 points.