Getting Tired of Sandwiches

I am so tired of bringing sandwiches to work. The problem is that when I eat the sandwiches at lunch, most of the components of the sandwich has already deteriorated. E.g. the salad is dry, the bread has become soggy, and the ham smells. The alternative is to eat at restaurants. The problem with this is that it often costs quite a lot to eat out and I feel guilty not saving money.

What I need is a simple-to-prepare lunch that is tasty and healthy. I am thinking of bringing to work sandwiches with Vegemite on them. I have heard that Vegemite has too much salt in it. However, the New Vegemite contains less salt and apparently it tastes better.