When I pack for vacation, I bring a minimal-but-complete sewing setup with me.
This consists of:
Folding adjustable table (for the machine)
Sewing machine w/bed extension
18x24 cutting mat
45mm rotary blade (though I prefer 60mm at home)
6.5x24 ruler (my favorite ruler by far)
Thread
thread snips
seam ripper
travel iron
travel ironing mat
I don't usually do any actual quilting on vacation because I bring a small machine. If I were to plan to do quilting I'd also include quilting gloves and one of those blue water-erase markers.
If I were planning on finishing a quilt all the way to doing binding, I'd also bring some larger shears for trimming the batting etc. off.
At HOME I keep a lot more "stuff". Normally I actually use 2 of the 6.5x24 rulers when I'm cutting; I also love my June Tailor rulers with the slots. If doing HST, bloc-loc rulers are great; and/or square-up rulers. I also agree largest cutting mat in budget is a great idea, I've upgraded mine and now have THE largest mat I can fit on my table and I love it.
I like to do foundation pieced crazy quilts that I then trim down to 12.5 blocks; so I have a 12.5" square ruler for that.