phpSysInfo is a customizable PHP Script that parses /proc, and formats information nicely. It will display information about system facts like Uptime, CPU, Memory, PCI devices, SCSI devices, IDE devices, Network adapters, Disk usage, and more.
Zabbix extension that reports various HDD status using various tools
This extension uses not only smartctl (smartmontools) but other available tools to determine the existance of an HDD and as much as possible of its status.
As a Zabbix "auto-discovery" process, these results can reflect changes in available HDD in near-to-real-time.