LinkStar H68K is a pocket-sized router (or mini PC) with Android, OpenWRT, Ubuntu, and Debian support - Liliputing
Amazon.com: GL.iNet GL-MT1300 (Beryl) VPN Wireless Little Travel Router – Connect to Hotel WiFi & Captive Portal, USB 3.0, 3 Gigabit Ports, Range Extender, Assess Point, Pocket-Sized, MicroSD Slot, Easy to Setup :
Amazon.com: TAKTIKAL 5G / 4G LTE Dual-Band Openwrt Wi-Fi Sim Router for Home & Business with 4 x 4 MU-MIMO, Band Lock, OpenVPN, Zero-Tier, & TTL - Plug and Play Connection on