If you’re a Windows user, you can remotely connect from your iPhone or iPad back to your PC using a Remote Desktop Client on your iOS device. I’ve found several pay RDC clients that are awesome, but Thinstuff iRdesktop also looks pretty promising. It’s free. Probably the biggest limitation is the level of encryption supported in this product vs. the pay products, but if you’re largely connecting from your couch, for instance, that should be less of an issue.