adjtimex (2)         - tune kernel clock
bdflush (2)          - start, flush, or tune buffer-dirty-flush daemon
btrfstune (8)        - tune various btrfs filesystem parameters
dev_fill_metadata_dst (9) - Retrieve tunnel egress information.
getunwind (2)        - copy the unwind data to caller's buffer
gpgmailtunl (1p)     - Encrypts an email message into the body of another email.
ip (8)               - show / manipulate routing, devices, policy routing and...
ip-l2tp (8)          - L2TPv3 static unmanaged tunnel configuration
ip-tunnel (8)        - tunnel configuration
mewstunnel (1)       - stunnel wrapper for Mew
plipconfig (8)       - fine tune PLIP device parameters
reiserfstune (8)     - The tunning tool for the ReiserFS filesystem.
rrdtune (1)          - Modify some basic properties of a Round Robin Database
snd_ac97_tune_hardware (9) - tune up the hardware
stunnel (8)          - universal SSL tunnel
stunnel3 (8)         - universal SSL tunnel
stunnel4 (8)         - universal SSL tunnel
tune2fs (8)          - adjust tunable filesystem parameters on ext2/ext3/ext4...
tunelp (8)           - set various parameters for the lp device
xvidtune (1)         - video mode tuner for Xorg