Yes, nw you can do this.
Krunch, an online compression utility, provides you service to compress up to 10 files. You can also uncompress your files after uploading a compressed file. Other features include, uncompressing the compressed files present over web and similarily compressing online files.
I tried compressing 6 jpg files from my PC and there was 4.34% reduction in size after compressing the files in zip format whereas after compressing same files using winzip, there was 1KB more reduction, resulting into 4.57% of reduction – quite gud results. You can also mail your compressed file to your mail Id. So next time, you are visiting client location where there is no compression utility, dont worry, all you need to have a net conn. in order to get your huge logs compressed and mailed to your mail Id 😛