The Great Hunt: Your wastes of wedding cash - what should newlyweds avoid?

Having recently got married (and dealt with all the hilarious stress that went with it!) one thing I'd say you can do without is the expense of hiring a photo booth. It's a great idea, but who can't find other things they'd much rather spend £600 on?? We set up my digital SLR in a spare room at our venue and spent £15 on a RF Remote shutter control, £35 on an ornately framed blackboard (which we now have up in our kitchen to make shopping lists with) and £1 on a packet of chalk from the pound shop and ditched the idea of a guest book altogether. We used an old laptop that we weren't too worried about getting anything spilled on, and the software that came with my Canon to connect up to the camera, then all people had to do was write their message to the bride and groom and take their picture. Within a second or two they could see their photo from where they were standing (or sitting) and take another if they didn't like it. (We thought about the whole Polaroid thing, but realised you have to have someone there to take the pic for you, and that it could easily disappear into another room and get found at the end of the night in a corner without much use, OR you could spend a fortune on spare photo paper for it and end up with a load of useless and fuzzy pics at great expense). The pictures we ended up with are brilliant - we never knew how creative our friends and family are, especially with a few drinks in them!
Other things you can save on are table decorations - some people spend a fortune on those AND favours too. We got some kilner jars for £1 each from Ikea and filled them with sweets we bought in bulk at Makro and the sweet was the name for each table, so three jars on a table with sweets in and some paper striped sweetie bags from ebay made that super cheap! Also I had a heart-shaped paper punch that my mum had given me as a kid which I ended up using to punch a load of little hearts out as table confetti in our colour to help fill the table out a bit. That lot with a few tea lights and the glasses, cutlery etc looked great!
Also on flowers you don't have to go to a florist (although we thought for a table decoration we probably should) but for our bouquets and button holes we bought stems from a local garden centre that has a floristry section, and in total on flowers we spent about £200 (three bouquets of cala lilies, 5 button holes and one large table decoration for use when signing our register and was then transferred to the top table)
My bridesmaids dresses ended up coming from the sale rack at Marks and Spencer - we found the dresses online but then by the time we managed to get together to try them on they'd disappeared but were luckily still available in store and had been reduced three times to £25 each from £79 :T
My drop sparkly earrings were from a Sainsbury's Tu 25% off sale and with my nectar points cost me £1.50
I also made my own wedding cake - super stressful but really rewarding in the end! It was a 3 tier ruffled cake all in white with silk flowers from HobbyCraft on top and a wire MR & MRS topper from Etsy on top. It was HUGE and with all the practice bakes that I did (my work colleagues loved me in the run up to the wedding with all the cake I brought in for them to eat!) I think it probably cost about as much as having someone make one for us, but by the time I figured that bit out I was too far down the line! So if you want to save yourself the hassle, pay for one to be made, or ask a friend to do it for you - the last days before the wedding should be spent on getting your nails done and trying to make sure everything else is done rather than stressing about icing a cake!
See what your venue will throw in for free - cake stand and knife etc.
Hope this helps!