RC Flyers Toolkit Box is a handy toolbox for R/C pilots. It helps you manage batteries, flights, charge cycles, and check lists. It helps you keep track of which of your batteries are charged, where and when you have been flying last, how much went in your battery compared to the last cycle, what you have to pack to take with you, and which parts you have to check before flying. For rotary wing users, there is a pinion calculator that quickly gives you an idea about the RPM to be expected.
libguestfs is a set of tools for accessing and modifying virtual machine (VM) disk images. You can use this for viewing and editing files inside guests, scripting changes to VMs, monitoring disk used/free statistics, P2V, V2V, performing partial backups, cloning VMs, and much more. libguestfs can access nearly any type of filesystem including: all known types of Linux filesystem (ext2/3/4, XFS, btrfs, etc.), any Windows filesystem (VFAT and NTFS), any Mac OS X and BSD filesystems, LVM2 volumes, MBR and GPT disk partitions, raw disks, qcow2, CD and DVD ISO images, SD cards, and dozens more. libguestfs doesn't need root permissions.